Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Additional Questions

Students can Download Maths Chapter 3 Geometry Additional Questions and Answers, Notes Pdf, Samacheer Kalvi 8th Maths Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Additional Questions

Question 1.
State Pythagoras theorem.
Solution:
In a right angled triangle, the square on the hypotenuse is equal to the sum of the squares on the other two sides.

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Additional Questions

Question 2.
Write two uses of Pythagoras theorem in our daily life.
Solution:
The Pythagoras theorem is useful in finding the distance and the heights of objects.

Question 3.
Prove Pythagoras theorem.
Solution:
Proof of the Pythagoras theorem using similarity of triangles.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 add 1
Given: ∠BAC = 90°
To Prove BC2 = AB2 + AC2
Construction: Draw AD ⊥ BC
Proof:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 add 2
In ∆ ABC and ∆ DBA
∠B is common and ∠BAC = ∠ADB = 90°
Therefore, ∆ ABC ~ ∆ DBA, (AA similarity)
Hence, the ratio of corresponding sides are equal.
⇒ \(\frac{AB}{DB}\) = \(\frac{BC}{BA}\)
⇒ AB2 = BC x DB
Similarity, ∆ ABC ~ ∆ DAC,
⇒ \(\frac{AC}{DC}\) = \(\frac{BC}{AC}\)
⇒ AC2 = BC x DB
Adding (1) and (2), we get
AB2 + AC2 = BC x DB + BC x DC
= BC x (DB + DC) = BC x BC
⇒ AB2 + AC2 = BC2 and hence the proof of the theorem

Question 4.
State the converse of Pythagoras theorem.
Solution:
If in a triangle, the square on the greatest side is equal to the sum of squares on the other two sides, then the triangle is right angled triangle.

Question 5.
Give 2 examples for Pythagorean triplet.
Solution:
(21, 28, 35), (24, 32, 40)

Question 6.
Check whether (2, 3, 5) is Pythagorean triplet.
Solution:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 add 3
22 + 32 = 4 + 9 = 13
52 = 25
13 ≠ 25
∴ It is not a Pythagorean triplet.

Question 7.
Can the sides that measure 15 cm, 20 cm and 25 cm make a right triangle?
Solution:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 add 4
202 + 152 = 400 + 225 = 625
252 = 625
202 + 152 = 252
∴ It is Pythagorean triplet.
∴ The given sides make a right angled triangle.

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Additional Questions

Question 8.
In the figure, find the value of x.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 add 5
Solution:
In ABC
122 + 92 = 144 + 81 =225 = 152
∴ x = 15

Question 9.
In the figure find the value of a and b and verify ∆ ABD is a right angled triangle.
Solution:
Now by altitude – on – hypotenuse theorem,
AB2 = BC x BD gives
102 = a x 26
a = \(\frac{100}{26}\) = \(\frac{50}{13}\)
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 add 6
and AD2 = CD x BD
242 = b x 26
b = \(\frac{576}{26}\) = \(\frac{288}{13}\)
and in ∆ ABD;
AB2 + AD2 = BD2
102 + 242 = 576 = 262
BD = 26
Therefore ∆ ABD is a right angled triangle.

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Additional Questions

Question 9.
State the altitude-on-Hypotenuse theorem.
Solution:
If an altitude is drawn to the hypotenuse of an right angled triangle then (i) the two triangles are similar to the given triangle and also to each other.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 add 7
That is ∆ PRQ ~ ∆ PSR ~ ∆ RSQ

  1. h2 = xy
  2. p2 = yr and
  3. q2 = xr, where r = x + y

Samacheer Kalvi 9th English Grammar Active Voice, Passive Voice

You can Download Samacheer Kalvi 9th English Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 9th English Grammar Active Voice, Passive Voice

Read the following sentences and analyze the difference.
The team leader presented the report.
The report was presented by the team leader.

Samacheer Kalvi 9th English Grammar Active Voice, Passive Voice

  1. In the first sentence, the verb shows that the subject is the doer of the action. Therefore, the sentence is in active voice.
  2. In the second sentence, the verb shows that the subject is not the doer of the action. Therefore, the sentence is in passive voice.

We use the Passive voice when –

  • the focus is on the action rather than the doer of the action.
    (e.g.), About 50 percent of the graduates are employed in IT-related sectors.
  • we do not know who the doer is.
    (e.g.) My bike was stolen yesterday.
  • we talk of a system or a process.
    (e.g.) The vegetables are washed well. Then, they are cut into cubes.
  • we write newspaper headlines and notices at public places, (‘be’ verb is omitted as the language has to be concise)
    (e.g.) 20 sportsmen felicitated by PM.
  • we describe changes that have taken place.
    (e.g.) Our school looks completely different. The whole place has been painted.

Look at the table below. It shows the changes in tense while changing sentences from active voice in to passive voice.

TenseActive VoicePassive Voice
Simple PresentHe makes coffee.Coffee is made by him.
Present ContinuousHe is making coffee.Coffee is being made by him.
Present PerfectHe has made coffee.Coffee has been made by him.
Simple PastHe made coffee.Coffee was made by him.
Past ContinuousHe was making coffee.Coffee was being made by him.
Past PerfectHe had made coffee.Coffee had been made by him.
Simple FutureHe will make coffee.Coffee will be made by him.
Future PerfectHe will have made coffee.Coffee will have been made by him.

When using the active voice, the subjects are the ones performing the action.
God loves all men.
Birds build nests.
Dogs eats bones.

In these three sentences the subject does the action. Hence they are in the active voice. In the active voice, the verb takes an object.
All men are loved by God.
Nests are built by birds.
Bones are eaten by dogs.

Rules for changing Active Voice into Passive Voice:

  • Identify the subject, the verb and the object: SVO.
  • Change the object into subject.
  • Put the suitable helping verb or auxiliary verb according to the tense given.
  • Change the verb into past participle of the verb.
  • Add the preposition “by”
  • Change the subject into object.

Active Voice

Passive Voice

Columbus discovered America.

America was discovered by Columbus.

Who did this work?

By whom was this work done?

Open the window.

Let the window be opened.

He is writing a letter.

A letter is being written by him.

I will finish the work.

The work will be finished by me.

Somebody cleaned the room yesterday.

The room was cleaned yesterday.

How to form passive forms of verbs?

TenseActivePassive
Present Tensedo, doesis done (Singular) are done (Plural)
Past Tensedidwas done (Singular) were done (Plural)
Future Tensewill / can / may / must → dowill / can etc. → be done
Present Continuous Tenseam doing is doingis being done (Singular) are being done (Plural)
Past Continuous Tenseare doing was doingwas being done (Singular) were being done (Plural)
Future Continuous Tensewill be doing shall be doingNo Passive Voice
Present Perfect Tensehave done has donehave been done (Plural) has been done (Singular)
Past Perfect Tensehad donehad been done
Future Perfect Tenseshall have done will have donewill have been done
Present Perfect Continuous Tensehas been doing have been doingNo Passive Voice
Past Perfect Continuous Tensehad been doingNo Passive Voice
Future Perfect Continuous Tenseshall have been doing will have been doingNo Passive Voice

Samacheer Kalvi 9th English Grammar Active Voice, Passive Voice

Changes of Pronouns:

Active VoicePassive Voice
Ime
weus
youyou
hehim
sheher
itit
theythem

Type 1: Statements:

Active VoicePassive Voice
I write a letterA letter is written by me
We must keep the ruleThe rule must be kept by us
You bought a bookA book was bought by you
He closed the windowThe window was closed by him
She was writing lettersLetters were being written by her
I had posted a letterA letter had been posted by me
I do not drink teaTea is not drunk by me
She does not eat a mangoA mango is not eaten by her
1 Ie will have finished his workThe work will have been finished by him
They are digging a wellA well is being dug by them

Type 2: Imperative Sentence :
If the given sentence in the active voice is in the imperative, to get the passive voice use ‘Let’.
Passive Voice = Let + Object + be + Past Participle

Active VoicePassive Voice
Help meYou are requested to help me.
Sing a songLet a song be sung
Open the doorLet the door be opened
Don’t eat this fruitYou are warned not to eat this fruit.
  • We can begin the passive sentence with ‘you’ if we want to put emphasis on the person addressed to.

Type 3 : Interrogative Questions in the Passive :
If the question in the Active Voice begins with a Helping verb, the Passive voice must also begin with a suitable helping verb. Supposing the question begins with ‘Wh or How’ form (what, when, how …) the Passive Voice must begin with the same.

Active VoicePassive Voice
Are you writing a letter?Is a letter being written by you?
Is she beating the child?Is the child being beaten by her?
Will you accept the position?Will the position be accepted by you?
Who broke the window?By whom was the window broken?
Why did you write such a letter?Why was such a letter written by you?
Where can you hide this box?Where can this box be hidden by you?

If a sentence contains two objects namely Indirect Object and Direct Object in the Active Voice, two forms of Passive Voice can be formed.

  • She brought me a cup of coffee. (AV)
    I was brought a cup of coffee by her. (PV) (or)
    A cup of coffee was brought to me by her. (PV)
  • The teacher teaches us grammar. (AV)
    We are taught grammar by the teacher. (PV) (or)
    Grammar is taught [to] us by the teacher. (PV)

Infinitive and Gerund :

  • I want to shoot the tiger. (AV)
    I want the tiger to be shot. (PV)
  • I remember my father taking me to the theatre. (AV)
    I remember being taken to the theatre by my father. (PV)

Samacheer Kalvi 9th English Grammar Active Voice, Passive Voice

Passive to Active form:
While changing Passive Voice into Active Voice, we must keep in mind all the rules of the Active Voice in the reverse order. We come across sentences in the Passive Voice without subject or agent. In this case, supply the appropriate subject.

Changing Passive Voice to Active Voice.

Passive VoiceActive Voice
The thief was finally arrested.The police finally arrested the thief.
We were taught grammar.The teacher taught us grammar.
My purse has been stolen.Somebody has stolen my purse.
The patients have looked after.The doctor looked after the patients.
  • Last year, the Swach Bharat scheme was announced by the Government.
  • Rare plants are found in Silent Valley.

In the first sentence, the doer/agent is explicitly mentioned because the doer is important in that sentence. But in the second sentence, it is not so, because either the agent or doer of the action is too obvious or unknown.

The passive construction is quite common in scientific/technical/ business writing. In these types of objective writing, the emphasis is usually on the action or process or thing that is described. So the ‘by’ phrase is generally omitted in these writings. It is called Impersonal Passive.

  • They say that might is right.
    It is said that might is right.
  • One finds mosquitoes everywhere.
    Mosquitoes are found everywhere.
  • He gave us a cheque.
    A cheque was given to us.

Exercises
(i) Choose the correct passive form for the following sentences in active voice.

1. I did not beat her.
(a) She is not beaten by me.
(b) She has not beaten by me.
(c) She was not beaten by me.
Answer:
(c) She was not beaten by me.

2. I will never forget this experience.
(a) This experience is not forgotten by me.
(b) This experience would never be forgotten by me.
(c) This experience will never be forgotten by me.
Answer:
(c) This experience will never be forgotten by me.

3. Mother made a cake yesterday.
(a) A cake made by mother yesterday.
(b) A cake is made by mother yesterday,
(c) A cake was made by mother yesterday.
Answer:
(c) A cake was made by mother yesterday.

4. The boy congratulated the girl.
(a) The girl was congratulated by the boy.
(b) The girl had congratulated by the boy.
(c) The girl congratulated the boy.
Answer:
(a) The girl was congratulated by the boy.

5. Did she do her duty?
(a) Was she done her duty?
(b) Was her duty done by her?
(c) Had her duty done by her?
Answer:
(b) Was her duty done by her?

6. The tiger was chasing the deer.
(a) The deer was chased by the tiger.
(b) The deer was being chased by the tiger,
(c) The deer had chased by the tiger.
Answer:
(b) The deer was being closed by the tiger

Samacheer Kalvi 9th English Grammar Active Voice, Passive Voice

7. She has written a novel.
(a) A novel has written by her.
(b) A novel has been written by her.
(c) A novel had written by her.
Answer:
(b) A novel has been written by her.

8. She has learned her lessons.
(a) Her lessons has learned by her.
(b) Her lessons have been learned by her.
(c) Her lessons had been learned by her.
Answer:
(b) Her lessons have been learned by her.

9. Have you finished the report?
(a) Has the report finished by you?
(b) Has the report been finished by you?
(c) Had the report been finished by you?
Answer:
(b) Has the report been finished by you?

10. The police have caught the thief.
(a) The thief has been caught by the police.
(b) The thief was caught by the police.
(c) The thief had been caught by the police.
Answer:
(a) The thief has been caught b– police,

(ii) Rewrite the following sentences into active voice.

1. We are taught grammar by Mr. Harsha.
Answer:
Mr. Harsha teaches us grammar.

2. He was praised by the teacher.
Answer:
The teacher praised him.

3. The injured were taken to the hospital by the firemen.
Answer:
The firemen took the injured to the hospital.

4. The town was destroyed by an earthquake.
Answer:
An earthquake destroyed the town.

5. The teacher was pleased with the boy’s work.
Answer:
The boy’s work pleased the teacher.

6. The building was damaged by the fire.
Answer:
The fire damaged die building.

7. By whom were you taught Hindi?
Answer:
Who taught you Hindi? ,

8. You will be given a ticket by the manager.
Answer:
The manager will give you a ticket.

9. The streets were thronged with spectators.
Answer:
Spectators thronged the streets.

Samacheer Kalvi 9th English Grammar Active Voice, Passive Voice

10. We will be blamed by everyone.
Answer:
Everyone will blame us.

11. The trees were blown down by the wind.
Answer:
The wind blew down the trees.

12. The thieves were caught by the police.
Answer:
The police caught the thieves.

13. The letter was posted by Alice.
Answer:
Alice posted the letter.

14. We were received by the hostess.
Answer:
The hostess received us.

15. The snake was killed with a stick.
Answer:
They / somebody killed the snake with a stick.

16. The minister was welcomed by the people.
Answer:
The people welcomed the minister.

17. He was found guilty of murder.
Answer:
They found him guilty of murder.

18. This house was built by Afsar.
Answer:
After wilting this house.

(iii) Rewrite the following sentences in the passive voice.

1. She is writing a poem.
Answer:
A poem is being written by her.

2. The team has won the series.
Answer:
The series has been won by the team.

3. Can you break the door?
Answer:
Can the door be broken by you?

Samacheer Kalvi 9th English Grammar Active Voice, Passive Voice

4. Will she sing a song?
Answer:
Will a song be sung by her?

5. Is he speaking English?
Answer:
Is English being spoken by him?

6. Are you eating a banana?
Answer:
Is a banana being eaten by you?

7. Why are you washing the car?
Answer:
Why is the car being washed by you ?

8. When will he give the money?
Answer:
When will the money be given by him?

9. Where will he meet you?
Answer:
Where will you be met by him?

10. How do you make a cake?
Answer:
How is a cake made by you?

11. Who did you tell the story?
Answer:
To whom was the story told by you?

12. Lighting struck him.
Answer:
He was struck by lighting.

13. The language that he used quite shocked me.
Answer:
I was quite shocked by the language that he used.

14. We were both filled with horror by the sight of that event.
Answer:
The sight of the event filled both of us with horror.

15. I was much hurt by his voice and manner.
Answer:
His voice and manner hurt me much.

16. They were welcomed back by the city on their return.
Answer:
The city welcomed back them on their return.

17. He was punished by the master for speaking in the class. ‘
Answer:
The master punished him for speaking in class.

18. Many objections were raised by us to the plan that was proposed by him.
Answer:
He proposed many plans that we raised many objections.

Samacheer Kalvi 9th English Grammar Active Voice, Passive Voice

19. Will he not be persuaded to work harder by a sense of duty?
Answer:
Will a sense of duty not persuade him to work?

20. I was called upon by the meeting to give my reasons.
Answer:
The meeting called upon me to give my reasons.

21. He was known by me by his voice when I was spoken to by him in the dark.
Answer:
I knew him by his voice when he spoke to me in the dark.

22. His return was not expected by us.
Answer:
He did not expect his return.

(iv) Complete these sentences with the verbs in brackets. Use the present simple passive.

I. E-mails _________ and received by most internet users. (send)
Answer:
are sent

2. Information about goods and services _________ (find)
Answer:
is found

3. Go&ls and services _________ in e-shops. (buy)
Answer:
are bought

4. Online newspapers and magazines _________ mostly by adult users. (read)
Answer:
are read

5. The internet _________ for social networking, especially by young people. (use)
Answer:
is used

6. relephone and video calls _________ (make)
Answer:
are made

7. Videos and films _________ (watch)
Answer:
are watched

8. Listening and music streaming activities _________ (cany out)
Answer:
are carried out

Samacheer Kalvi 9th English Grammar Active Voice, Passive Voice

9. Hotel accommodation _________ by travellers. (search for)
Answer:
is searched for

10. Financial transactions through internet banking _________ (do)
Answer:
are done

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.2

Students can Download Maths Chapter 3 Geometry Ex 3.2 Questions and Answers, Notes Pdf, Samacheer Kalvi 8th Maths Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.2

Miscellaneous Practice Problems

Question 1.
The sides of a triangle are 1.2 cm, 3.5 cm and 3.7cm. Is this triangle a right triangle? If so, which side is the hypotenuse?
Solution:
The sides of a triangle are a = 1.2 cm; b = 3.5 cm; c = 3.7 cm
By Pythagoras theorem,
c2 = a2 + b2
a2 + b2 = 1.22 + 3
52 – 1.44 +12.25 = 13.69
c2 = 3.72 = 13.69
(1) = (2)
Yes, it is a right angled triangle. The hypotenuse c = 3.7 cm.

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.2

Question 2.
Rithika buys an LED TV which has a 25 inches screen. If its height is 7 inches, how wide is the screen? Her TV cabinet is 20 inches wide. Will the TV fit into the cabinet? Why?
Solution:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.2 1
Take the sides of a right angled triangle ∆ ABC as
a = 7 inches
b = 25 inches
c = ?
By Pythagoras theorem,
b2 = a2 + c2
25 = 72 + c2
c2 = 252 – 72 = 625 – 49 = 576
∴ c2 = 242
⇒ c = 24 inches
∴ Width of TV cabinet is 20 inches which is lesser than the width of the screen ie.24 inches. The TV will not fit into the cabinet.

Question 3.
Find the length of the support cable required to support the tower with the floor.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.2 2
Solution:
From the figure, by Pythagoras theorem,
x2 = 202 + 152 = 400 + 225 = 625
x2 = 252 ⇒ x = 25ft.
∴ The length of the support cable required to support the tower with the floor is 25 ft.

Question 4.
A ramp is constructed in a hospital as shown. Find the length of the ramp.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.2 3
Solution:
Take a = 7 ft ; b = 24 ft.
By Pythagoras theorem,
l2 = c2 + b2
= 72 + 242 = 49 + 576
l = 25ft

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.2

Question 5.
In the figure, find MT and AH
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.2 4
Solution:
By Pythagoras theorem,
MT2 = MH2 + HT2
= 602 + 802 = 3600 + 6400
= 10000 = 1002
∴ MT = 100
By the altitude – on – hypotenuse theorem,
MH2 = MA x MT
602 = MA x 100
MA = \(\frac{3600}{100}\) = 36
∴ In ∆ MAH, by Pythagoras theorem,
AH2 = MH2 – MA2
= 602 – 362 = 3600 – 1296 = 2304 = 482
∴ AH = 48
∴ Ans MT = 100
AH = 48

Challenging Problems

Question 6.
Mayan travelled 28 km due north and then 21 km due east. What is the least distance that he could have travelled from his starting point?
Solution:
From the figure AC is to be found.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.2 5
By using Pythagoras theorem,
AC2 = AB2 + BC2
= 282 + 212 = 784 + 441 = 1225 = 352
∴ AC = 35 km
This is the least distance that he could have travelled from his starting point.

Question 7.
If ∆ APK is an isosceles right angled triangle, right angled at K. Prove that AP2 = 2AK2.
Solution:
From the figure, ∆ APK is a right triangle.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.2 6
By using Pythagoras theorem,
AP2 = AK2 + PK2
= AK2 + AK2 (since it is an isosceles A)
= 2AK2
Hence it is proved.

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.2

Question 8.
The diagonals of the rhombus is 12 cm and 16 cm. Find its perimeter. (Hint: the diagonals of rhombus bisect each other at right angles).
Solution:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.2 7
Here AO = CO = 8 cm
BO = DO = 6 cm
(∴ the diagonals of rhombus bisect each other at right angles)
∴ In ∆ AOB,
AB2 = AO2 + OB2 = 82 + 62 = 64 + 36
= 100 = 102
∴ AB = 10
Since it is a rhombus, all the four sides are equal.
AB = BC = CD = DA
∴ Its Perimeter = 10 + 10 + 10 + 10 = 40 cm

Question 9.
In the figure, find AR.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.2 8
Solution:
∆ AFI, ∆ FRI are right triangles.
By Pythagoras theorem,
AF2 = AT2 – FT2 = 252 – 152
= 625 – 225 = 400 = 202
∴ AF = 20 ft ….(1)
FR2 = RI2 – FI2 = 172 – 152 = 289 – 225 = 64 = 82
FR = 8 ft.
∴ AR = AF + FR = 20 + 8 = 28 ft.

Question 10.
∆ ABC is a right angled triangle in which ∠A = 90° and AM ⊥ BC. Prove that AM = \(\frac{ABxAC}{BC}\). Also if AB = 30 cm and AC = 40 cm, find AM.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.2 9
Solution:
Given: ∆ ABC is a right angled triangle.
∠A = 90, AM ⊥ BC
To Prove: AM = \(\frac{ABxAC}{BC}\)
Proof:
In the given figure, Area of the triangle A ABC [taking AB as base and AC as height]
= \(\frac{1}{2}\) x AB x AC ….(1)
And also, Area of the triangle ∆ ABC [taking BC as base and AM as height]
= \(\frac{1}{2}\) x BC x AM ……(2)
Since (1) & (2) are the same, we can equate (2) and (1)
i.e. \(\frac{1}{2}\) x BC x AM = \(\frac{1}{2}\) x AB x AC
AM = \(\frac{ABxAC}{BC}\)
Hence proved. If AB = 30 cm, AC = 40 cm
By Pythagoras theorem, BC2 = AB2 + AC2 = 302 + 402 = 900 + 1600 = 2500 = 502
∴ BC = 50
Using the altitude – on – hypotenuse theorem
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.2 10
Here AC2 = MC x BC
402 = MC x 50
∴ BM = BC – MC = 50 – 32 = 18 cm
AM2 = BM x MC = 18 x 32 = 576 = 242
∴ AM = 24 cm

Samacheer Kalvi 9th English Grammar Determiners

You can Download Samacheer Kalvi 9th English Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 9th English Grammar Determiners

Observe the nouns in the following sentences and words before them.

  • An apple is a healthy fruit.
  • Two cats have drunk a bowl of milk,
  • My father has many cars.

Determiners are the words that introduce a noun and provide some information about it (but do not describe it). .
Determiners are followed by a noun.

  • The ball
  • Five cats
  • His son
  • Some students

Types of Determiners
Samacheer Kalvi 9th English Grammar Determiners 1

  • The quantifiers all, any, enough, less, a lot of, more, most, no, none of, some etc., are used with both countable and uncountable nouns.
  • The quantifiers both, each, either, fewer, neither etc., are used only with countable nouns.

ARTICLES

Articles are bifurcated into
(i) Definite Article (the) and
(ii) indefinite articles (a, an).

(i) DEFINITE ARTICLE : When to use “THE”

❖ General Rules
Use the to refer to something which has already been mentioned.

Examples :
On Monday, an unarmed man stole 10,000 from the bank. The thief hasn’t been caught yet.
I was walking past Benny’s Bakery when I decided to go into the bakery to get some bread.

Use the when you assume there is just one of something in that place, even if it has not been mentioned before.

Examples :
We went on a walk in the forest yesterday.
Where is the bathroom?
Turn left and go to number 45. Our house is near the restaurant.
My father enjoyed the book you gave him.

(ii) INDEFINITE ARTICLES : When to use “a” and “an”.

In English, the two indefinite articles are a and an.
Like other articles, indefinite articles are invariable.

You use one or the other, depending on the first letter of the word following the article, for pronunciation reasons. Use a when the next word starts with a consonant, or before words starting in u and eu when they sound like you. Use an when the next word starts with a vowel (a, e, i, o, u) or with a mute h.

Examples :
a boy, an apple, a car, a helicopter, an elephant, a big elephant, an itchy sweater, an ugly duck, a European, a university, a unit, an hour, an honour.

The indefinite article is used to refer to something for the first time or to refer to a particular member of a group or class. Some use cases and examples are given below.

  1. Would you like a drink?
  2. I’ve finally got a good job.
  3. An elephant and a mouse fell into the well.

Example :

  1. Mary is training to be an engineer.
  2. John is an Englishman
  3. I’d like an orange and two lemons please.

Samacheer Kalvi 9th English Grammar Determiners

Demonstratives
Demonstratives show where an object, event, or person is in relation to the speaker. They can refer to a physical or a psychological closeness or distance. When talking about events, the near demonstratives are often used to refer to the present while the far demonstratives often refer to the past.

Near the speakerFar from the speaker
AdverbHereThere
Demonstrative with singular nouns & uncountable nounsThisThat
Demonstrative with plural countable nounsTheseThose

Examples:

Near the speakerFar from the speaker
Is this John’s house?Is that John’s house over there?
This is a nice surprise!That must have been a nice surprise for you.
These apples are mine.Those apples are yours.
What are you up to these days?Those days are long gone.
This time I won’t be late.We really surprised you that time.
This sugar is for my crepes.You can use that sugar for your cake.

Possessive Adjectives (Determiners)

Possessive adjectives are not pronouns, but rather determiners. It is useful to learn them at the same time as pronouns, however, because they are similar in form to the possessive pronouns. Possessive adjectives function as adjectives, so they appear before the noun they modify. They do not replace a noun as pronouns do.

Examples :
Did mother find my shoes?
The teacher wants to see your homework.
Samantha will fix her bike tomorrow.
The cat broke its leg.
This is our house.
Where is their school?

Possessive Pronouns

Possessive pronouns replace possessive nouns as either the subject or the object of a clause. Because the noun being replaced doesn’t appear in the sentence, it must be clear from the context.

Examples :
This bag is mine.
Yours is not blue.
That bag looks like his.
These shoes are not hers.
That car is ours.
Theirs is parked in the garage.

Samacheer Kalvi 9th English Grammar Determiners

Reflexive & Intensive Pronouns

Reflexive and intensive pronouns are the same set of words but they have different functions in a sentence.

Reflexive pronouns refer back to the subject of the clause because the subject of the action is also the direct or indirect object. Only certain types of verbs can be reflexive. You cannot remove a reflexive pronoun from a sentence because the remaining sentence would be grammatically incorrect.

Examples :
I told myself to calm down.
You cut yourself on this nail?
He hurt himself on the stairs.
She found herself in a dangerous part of town.
The cat threw itself under my car!
We blame ourselves for the fire.
The children can take care of themselves.

Quantifiers
Quantifiers are adjectives and adjectival phrases that give approximate or specific answers to the questions “How much?” and “How many?” The pages in this section will teach you more about the different quantifiers in English and how they are used.

  • Numbers in English: ordinal, cardinal, and percentages
  • To answer the questions How much? and How many? certain quantifiers can be used with countable nouns (friends, cups, people), others with uncountable nouns (sugar, tea, money) and still others with all types of nouns.
Only with uncountable nounsWith all types of nounsOnly with countable nouns
a littleno, none, not anya few
a bit ofsomea number of
anyseveral
a great deal ofa lot of, lots ofa great number of
a large amount ofplenty ofa large number of

Examples :
Would you like some tea and a few cookies?
I always put a little milk and some carrots in my soup.
He has several apples. I don’t have any fruit at all.
She has plenty of clothes for the winter.
I received a large amount of feedback from my survey.

Cardinal Numbers
A Cardinal Number says how many of something there are, such as one, two, three, four, five, etc.
A Cardinal Number answers the question “How Many?”

Examples :
There are twenty children in the class.
He purchased two books.
There are five plates on the table.
Sumitha is fourteen years old.

Ordinal Numbers

An Ordinal Number tells us the position of something in a list, such as first, second, third, fourth, fifth and so on.
Examples :
Let us begin with the first chapter.
We live in the fourth house on the right.
I was bom on the fifteenth of January.
He got the second prize.

Exercises

1. Fill in the blanks with appropriate determiners,
1. Our garden looks awful this summer. There are too ____________ weeds
Answers:
many

2. There aren’t ____________ flowering plants in our garden.
Answers:
many

3. How ____________ pages did you read?
Answers:
many

4. They say ____________ knowledge is a dangerous thing.
Answers:
a little

5. I am having ____________ trouble passing my driving exam.
Answers:
a lot of

6. ____________ people can afford a home these days.
Answers:
few

Samacheer Kalvi 9th English Grammar Determiners

7. You have ____________ patience
Answers:
little

8. She earns ____________ money than i do
Answers:
less

9. ____________ of the information proved to be outdated.
Answers:
some

10. I didn’t use ____________ fertilizer last spring.
Answers:
much

Choose the correct determiner.
1. There are chairs in this room than in the other room, (more / much)
Answer:
more

2. The assistant didn’t give information, (much / many)
Answer:
much

3. After the negotiations, they made changes in their proposal, (little/few)
Answer:
few

4. mosquitoes appeared after the rain. (A large amount of / A great number of)
Answer:
A great number of

5. Toned Milk has calories than Full Cream Milk, (less / fewer)
Answer:
fewer

6. students taking TOEFL is increasing. (The amount of / The number of)
Answer:
The number of

7. The case had to be reconsidered with new evidence, (these / this)
Answer:
this

8. I like to eat food, (many / a lot of)
Answer:
A lot of

9. She ate French–fries than usual, (fewer / less)
Answer:
fewer

10. He wants to make as money as possible, (much / many)
Answer:
much

11. Vini invited a large of people to the party, (amount/number)
Answer:
number

12. Raji will drink an endless of milk if you let her. (amount / number)
Answer:
Amount

Fill in the blanks with a, an, the, or leave the blank.
1. Han is earning Rupees 1000 _____ hour at the Food court.
Answer:
an

Samacheer Kalvi 9th English Grammar Determiners

2. Janani makes it ______ habit to buy clothes on sale.
Answer:
a

3. To tell ______ truth, a bank savings account may not be the best place for your money.
Answer:
the

4. Hemá showed initiative when she decided to start a business of her own.
Answer:
an

5. Losing as little as ______ quart of blood can result in shock and unconsciousness.
Answer:
a

6. Over last 20 years, more than 3 million people have visited ______ theme park.
Answer:
the, the

7. Major changes have taken place in ______ Educational services.
Answer:
the

8. Dr. Richards predicts ______ extinction of the whooping crane.
Answer:
th

9. Taking a hot bath is ______ good way to relax.
Answer:
a

Samacheer Kalvi 9th English Grammar Determiners

Samacheer Kalvi 9th English Grammar Reported Speech (Direct to Indirect Speech)

You can Download Samacheer Kalvi 9th English Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 9th English Grammar Reported Speech (Direct to Indirect Speech)

Quoting the exact words of the speaker is called “The Direct Speech”.

David said, “I am writing a letter now”.

Reporting of what a speaker said without quoting his exact words is called ‘Indirect Speech’, (also called Reported Speech).

David said that he was writing a letter then.

The following table suggests the words that change during a transformation.

Direct SpeechIndirect Speech
nowthen
herethere
here afterthere after
thisthat
thesethose
agobefore
thusso
to-daythat day
to-nightthat night
last nightthe previous night
yesterdaythe day before (or) the previous day
tomorrowthe next day (or) the following day
last weekthe week before (or) the previous week
next weekthe week after (or) the following week
last monththe month before (or) the previous month
next montha month after

If the reporting verb is in the Present or Future tense (e.g., say, will say) there is no change in the tense of the verb in the Indirect speech.

Anto says, “I eat a mango”. (Direct Speech)
Anto says that he eats a mango”. (Indirect Speech)

Samacheer Kalvi 9th English Grammar Reported Speech (Direct to Indirect Speech)

If Reporting Verb is in the Past Tense, the tense of the verbs in the reported speech or Indirect Speech must be generally changed.
1. Present Tense in the Direct becomes past tense.
Janis said, “I write a letter”. (D.S)
Janis said that she wrote a letter. (I.S)

2. Past Tense in the Direct becomes past perfect or remains unchanged.
Arun said, “I bought a pen yesterday”. (D.S)
Arun said that he had bought a pen the previous day. (I.S)

3. Present Continuous in the Direct becomes past continuous.
Juber said, “I am going to mosque”. (D.S)
Juber said that he was going to mosque. (I.S)

4. Past Continuous in the Direct becomes past perfect continuous. *
Nelson said, “I was playing cricket”. (D.S) > M
Nelson said that he had been playing cricket. (I.S)

5. Present Perfect in the Direct becomes past perfect.
Kamal said, “I have done my home work”. (D.S)
Kamal said that he had done his home work. (I.S)

6. Present Perfect Continuous in the Direct becomes past perfect continuous.
He said, “I have been reading a novel”. (D.S)
He said that he had been reading a novel. (I.S)

7. ‘Will’ and ‘Shall’ are changed to ‘would’.
He said, “I will go to Trichy tomorrow”. (D.S)
He said that he would go to Trichy the next day. (I.S)

8. may – might
can – could
must – had to (or) must
Nisha said, “I must go now”. (D.S)

Nisha said that she must go then, (or) Nisha said that she had to go then. (I.S)

Hint: Past Perfect and Past Perfect Continuous in the Direct Speech do not take any change *, in their tenses.

Exception to the above rule:
If the direct speech contains the Universal Truth, the tense of the direct speech remains unchanged even if the reporting verb is in the past.

The teacher said, “The sun rises in the East”. (D.S)
The teacher said that the sun rises in the East. (I.S)

Statement (Or) Assertive Sentence

Rules:
Remove the quotation marks in the statement
Use the conjunction ‘that’
Change the reporting verb ‘say to’ into ‘tell’
Change the reporting verb ‘said to’ into ‘told’ ‘

Note: He said that (correct)
He told me that (correct)
He told that (Incorrect)

Samacheer Kalvi 9th English Grammar Reported Speech (Direct to Indirect Speech)

1. “I will work hard to get first-class” said Nasser (D.S.)
Nasser said that he would work hard to get first class. (I.S.)

2. “You can do this work” said Sundar to Kumar (D.S.)
Sundar told Kumar that he could do that work. (I.S.)

3. He says, “I am glad to be here this evening”(D.S.)
He says that he is glad to be there that evening. (I.S.)

4. “I‘m going to the library now” said David (D.S.)
David said that he was going to the library then. (I.S.)

Imperative Sentence (Order Or Request)

Rules:
Remove the quotation marks in an imperative sentence.
Use ‘to’ if it is an affirmative sentence, (without don’t)
Use ‘not to’ if the sentence is negative, (with don’t)
Don’t use ‘that’
Omit the word ‘please’. Use the word ‘request’ instead of ‘say’.

If the direct speech contains a request or a command, the reporting verb (say, said) change to tell, request, order, command etc. in its correct tense.

1. “Don’t talk in the class” said the teacher to the boys. (D.S.)
The teacher advised the boys not to talk in the class. (I.S.)

2. “Please give me something to eat. I am hungry” the old man said to them. (D.S.)
The old man requested them to give him something to eat and said that he was hungry (I.S.)

3. “Be careful” said he to her. (D.S.)
He warned her to be careful. (I.S.)

4., “Bring me a cup of tea” said Danush to Andrea. (D.S.)
Danush asked Andrea to bring him a cup of tea. (I.S.)

Interrogative Sentence (Questions)

Rules:
Remove the quotation marks and the question mark in the interrogative sentence.
Use ‘if’ or ‘whether’ if the sentence inside the quotation marks begins with a helping verb (Auxiliary verb).
Use the given interrogative word (what, when, where, why, who, whom, whose, which, now etc.) if it does not begin with the helping verb.
Don’t use ‘that’
Changing the reporting verb (say, said) into ‘ask’ or ‘enquire’ in its correct tense.
Omit helping verb like ‘do, does, did’. But don’t omit them when they are with ‘not’.

1. “Won’t you help me to carry this box?” said I to my friend. (D.S.)
I asked my friend if he would not help me to carry that box. (I.S.)

2. Mohan said to Stalin, “Why did not you attend the meeting yesterday”? (D.S.)
Mohan asked Stalin why he had not attended the meeting the day before. (I.S.)

3. “How often do you go to the theatre?” said David to John. (D.S.)
David asked John how often he went to the theatre. (I.S.)

4. Mohamed said to Sultan, “Do you like mangoes?” (D.S.)
Mohamed asked Sultan if he liked mangoes. (I.S.)

Exclamatory Sentence

Rules:
Remove the quotation marks and exclamatory mark.
Change the exclamatory sentence into Statement or Assertive.
Use the conjunction ‘that’.
Omit the interjections such as Oh, O, Alas, how, what, hurrah.
Add the word ‘very’ to the adjective or adverb if necessary.
If the verb is not given, use ‘Be’ form verb (is, was, are, were, am) in its correct tense according to the subject.
Change the reporting verb (say, said) to ‘exclaim joyfully’
Use ‘exclaim’ sorrowfully for sorrowful incidents.

Samacheer Kalvi 9th English Grammar Reported Speech (Direct to Indirect Speech)

1. “O, what a beautiful flower that is!” said she. (D.S.)
She exclaimed joyfully that that was a very beautiful flower. (I.S.)

2. “What a horrible sight!” we all exclaimed. (D.S.)
We all exclaimed that it was a very horrible sight. (I.S.)

3. “Alas! I have broken my brother’s watch” said he.
He exclaimed sorrowfully that he had broken his brother’s watch. (I.S.)

4. “How beautiful she is!” said Banu. (D.S.)
Banu exclaimed joyfully that she was very beautiful. (I.S.)

Direct Speech Into Indirect Speech

I. Look at the following examples of Direct and Indirect Speech:

1. He said, “Danny will be in London on Tuesday.”
He said that Danny would be in London on Tuesday.

2. “I never eat meat”, he explained.
He explained that he never ate meat.

3. He said, “I wish I knew.”
He said that he wished he knew.

4. She says, “I shall be there.”
She says that she would be there.

5. He said, “She is coming this week.”
He said that she was coming that week.

6. He said, “I bought this pearl for my mother.”
He said that he had bought that pearl for his mother.

7. He said, “Where is she going?”.
He asked where she was going.

8. He said, “Jaya, when is the next bus.”
He asked Jaya when the next bus was.

9. “Is anyone there?” she asked.
She asked if anyone was there.

10. The mother said, “Lie down, David.”
The mother asked David to lie down.

11. He said, “Don’t move, boys.”
He asked the boys not to move.

12. He said, “Please–say nothing about this.”
He asked her to say nothing about that.

Reported Speech–Statement–Rules

Whatever may be the tense of the Reporting Sentence, if the Reported Sentence tells a universal fact, no change is made in the tense of the Reported Sentence.

Example No. 1:
The mother is saying to the child, “The third day of the week is Tuesday. ”.
Step 1 : The Reported Sentence is: The third day of the week is Tuesday.
Step 2 : It is a Statement and a universal fact.
Step 3 : So, the conjunction word is — “that”.
Step 4 : ‘is saying to’ changes into ‘is telling’.
Step 5 : No change of pronoun.
Step 6 : It is a universal fact. So, no change of tense is necessary.
Step 7 : No change of extension.
‘Now, the Indirect Speech is:
The mother is telling the child that the third day of the week is Tuesday.

Samacheer Kalvi 9th English Grammar Reported Speech (Direct to Indirect Speech)

Example No. 2:
The History teacher says, “Megellan was the first navigator to come around the world. ”.

Step 1 : The Reported Sentence is: “Megellan was the first navigator to come around the world.”
Step 2 : It is a statement.
Step 3 : The conjunction word is — “that”.
Step 4 : ‘Says’ does not change. Use it as it is.
Step 5 : There are no pronouns to get changed.
Step 6 : No change of tense is made.
Step 7 : No extensive word to get changed.

Now, the Indirect Speech is:
The History teacher says that Megellan was the first navigator to come around the world.

Example No. 3:
You know the two types of Interrogative Sentences:
Inverted questions requiring ‘Yes’ or ‘No’ answers — 1st type.
Questions that begin with interrogative words — 2nd type
At first we shall deal with the First type:

Direct Speech: The boy said to the fruit–seller, “Are all these mangoes sweet?”
Step 1 : Identify the Reported Sentence.
Step 2 Know what kind of sentence the Reported Sentence is.
Step 3 Look for the correct Conjunction, (The Conjunction of the First type is “If or Whether”)
Step 4 Change of ‘said to’ — Since it is an interrogative sentence ‘said to ’ changes into ‘asked’.
Step 5 Step Look for the change of pronouns.
Step 6 Look for the change of tenses.

The Reporting Sentence is in past tense. The Reported Sentences is in present tense. So, the Reported Sentence should be changed into past tense, corresponding to the tense, of the Reporting Sentence.

The verb is ‘are’ — Its past tense is ‘were’.

Step 7 : Look for the change of extension words.
‘These’ changes into ‘those’.

The Indirect Speech is : The boy asked the fruit–seller if all those mangoes were sweet.

Example No 4:
Direct Speech: The grandfather said fo his grandsons, “Did you not like my story yesterday?”
SIeR 1 : The Reported Sentence is: “Did you not like my story yesterday?”
Step 2 : ‘It is an interrogative sentence. It is of the First type.
Step 3 : So its conjunction word is: ¡for Whether.
Step 4 : So ‘said to’ changes into ‘asked’.
Step 5 : Look for the pronouns.

(i) The first one is: ‘You’ (subject)
‘You’ — refers to grandsons. They are in the third person plural number.
So the third person of ‘You’ (subject, plural)
It is — ‘they’. ‘You’ changes into ‘they’.
‘You’ — grandsons — ‘They’
‘You’–they.

(ii) The next one is ‘My’.
‘My’ — refers to ‘the grandfather’ — in the third person.
So, take the third person of ‘My’
‘My’ changes into ‘His’.

Samacheer Kalvi 9th English Grammar Reported Speech (Direct to Indirect Speech)

Step 6 : Look for the change of tenses.
Step 7 : Extensive word ‘Yesterday’ changes into ‘the day before’. Now, the Indirect Speech is-

The grandfather asked his grandsons if they had not liked his story the day before.

Exercises
Transform the following questions into indirect form :

1. Radha asked, “Where are you going?”
Answer:
Radha asked (me) where I was going.

2. Mani asked, “Where are you going to spend the holiday?”
Answer:
Mani asked (me) where I was going to spend the holiday.

3. Jenifer said, “What will you do when you leave school?”
Answer:
Jennifer asked (me) what I would do when I left school.

4. The nurse asked the doctor, “How did you know my name?”
Answer:
The nurse wanted to know how the doctor had known her name.

5. The clerk said, “Do you have an appointment?”
Answer:
The clerk asked (me) whether/if I had an appointment.

6. Bharath said to his wife, “Have you seen my car keys?”
Answer:
Bharath asked his wife whether she had seen his car keys.

7. Rekha’s brother asked her, “Why didn’t you call me?”
Answer:
Rekha’s brother wanted to know why she hadn’t called him.

8. Rayan said to James, “Will you carry my briefcase for me please?”
Answer:
Rayan asked James to carry his briefcase.

9. Charles asked the receptionist, “When can I see the doctor?”
Answer:
Charles asked the receptionist when he could see the doctor.

10. Devi asked, “Where do you live?” ‘
Answer:
Devi asked (me) where I lived.

Change the following sentences into Indirect Speech:

1. He said, “I will do it now.”
Answer:
He said that he would do it then.

Samacheer Kalvi 9th English Grammar Reported Speech (Direct to Indirect Speech)

2. He says, “Honesty is the best policy.”
Answer:
He says that honesty is the best policy.

3. Ramesh says, “I have written a letter.”
Answer:
Ramesh says that he has written a letter.

4. She said, “Mahesh will be reading a book.”
Answer:
She said that Mahesh would be reading a book.

5. She said, “Where is your father?”
Answer:
She inquired where his father was.

6. He said to me, “Please take your book.”
Answer:
He requested me to take my book.

7. The Principal said to the peon, “Let this boy go out.”
Answer:
The Principal ordered the peon to let that boy go out.

8. He said to me, “May you live long!”
Answer:
He prayed that I might live long.

9. She said, “Goodbye friends!”
Answer:
She bade goodbye to her friends.

10. The student said, “Alas! I wasted my time last year.”
Answer:
The student regretted that he had wasted his time the previous year.

(iii) Change the following sentences into direct speech.

1. She asked me who was the best player..
Answer:
“Who is the best player here?”, she asked.

2. He asked me if I was going home with him.
Answer:
“Are you coming home with me?”, he asked.

3. She asked me what I wanted.
Answer:
She said to me, “What do you want?”.

Samacheer Kalvi 9th English Grammar Reported Speech (Direct to Indirect Speech)

4. He asked me what the matter was.
Answer:
He said to me, “What is the matter?”.

5. She enquired which her seat was.
Answer:
She said, “Which is my seat?”.

6. I asked whether he did not know the way home.
Answer:
I said, “Don’t you know the way home?”.

7. Aladdin asked the magician what he had done to deserve so severe a blow.
Answer:
Aladdin said to the magician, “What have I done to deserve so severe a blow?”

8. Ulysses asked the little bird whether it had anything to tell him.
Answer:
“Have you anything to tell me, little bird?”, asked Ulysses.

9. He asked me what my name was.
Answer:
He asked me, “What is your name?”.

10. The kind man asked the boy what he could do for him.
Answer:
“What can I do for you?”, the kind man asked the boy.

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.1

Students can Download Maths Chapter 3 Geometry Ex 3.1 Questions and Answers, Notes Pdf, Samacheer Kalvi 8th Maths Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.1

Question 1.
Fill in the blanks:

Question (i)
If in a ∆ PQR, PR2 = PQ2 + QR2, then the right angle of ∆ PQR is at the vertex ………
Answer:
Q
Hint:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.1 1

We have also given Lines and Angles concepts and problems for free of cost on our website.

Question:
(ii) If ‘l’ and ‘m’ are the legs and is the hypotenuse of a right angled triangle then, l2 = ……….
Answer:
n2 – m2
Hint:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.1 2

Question (iii)
If the sides of a triangle are in the ratio 5:12:13 then, it is ………
Answer:
a right angled triangle.
132 = 169
52 = 25
122 = 144
169 = 25 + 144
132 = 52 + 122
By Pythagoras theorem, In a right triangle, square of the hypotenuse is equal to the sum of the squares of other two sides.

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.1

Question (iv)
If a perpendicular is drawn to the hypotenuse of a right angled triangle, then each of the three pairs of triangles formed are …………
Answer:
Similar.

Question (v)
In the figure BE2 = TE x ………
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 1
Answer:
EN

Question 2.
Say True or False.

Question (i)
8, 15, 17 is a Pythagorean triplet.
Answer:
True
Hint:
172 = 289
152 = 225
82 = 64
64 + 225 = 289 ⇒ 172 = 152 + 82

Question (ii)
In a right angled triangle, the hypotenuse is the greatest side.
Answer:
False
Hint:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 2

Question (iii)
One of the legs of a right angled triangle PQR having ∠R = 90° is PQ.
Answer:
False
Hint:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 3
In ∆ PQR, QR and RP are legs and PQ is the hypotenuse

Question (iv)
The hypotenuse of a right angled triangle whose sides are 9 and 40 is 49.
Answer:
False
Hint:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 4
492 = 2401
92 = 81
402 = 1600
402 + 92 = 1600 + 81 + 1681
492 = 2401
2401 ≠ 1681

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.1

Question (v)
Pythagoras theorem is true for all types of triangles.
Answer:
False
Hint:
Pyhtagoras theorem is true for only right angled triangles.

Question 3.
Check whether given sides are the sides of right – angled triangles, using Pythagoras theorem,

  1. 8, 15, 17
  2. 12, 13, 15
  3. 30, 40, 50
  4. 9, 40, 41
  5. 24, 45, 51

Solution:
1. 8, 15, 17
Take a = 8,
b = 15 and
c = 17
Now a2 + b2 = 82 + 152 = 64 + 225 = 289
172 = 289 = c2
∴ a2 + b2 = c2
By the converse of Pythagoras theorem, the triangle with given measures is a right angled triangle.
Answer:
yes.

2. 12, 13, 15
Take a = 12
b = 13 and
c = 15
Now a2 + b2 = 122 + 132 = 144 + 169 = 313
152 = 225 ≠ 313
By the converse of Pythagoras theorem, the triangle with given measures is not a right angled triangle.
Answer:
No.

3. 30, 40, 50
Take a = 30
b = 40 and
c = 50
Now a2 + b2 = 302 + 402 = 900 + 1600 = 2500
c2 = 502 = 2500
∴ a2 + b2 = c2
By the converse of Pythagoras theorem, the triangle with given measures is a right angled triangle.
Answer:
yes.

4. 9, 40, 41
Take a = 9
b = 40 and
c = 41
Now a2 + b2 = 92 + 402 = 81 + 1600= 1681
c2 = 412 = 1681
∴ a2 + b2 = c2
By the converse of Pythagoras theorem, the triangle with given measures is a right angled triangle.
Answer:
Yes.

5. 24, 45, 51
Take a = 24
b = 45 and
c = 51 Now
a2 + b2 = 242 + 452 = 576 + 2025 = 2601
c2 = 512 = 2601
a2 + b2 = c2
By the converse of Pyhtagoreas theorem, the triangle with given measure is a right angled triangle.
Answer:
Yes.

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.1

Question 4.
Find the unknown side in the following triangles.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 5
Solution:
(i) From ∆ ABC, by Pythagoras theorem
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 6
BC2 = AB2 + AC2
Take AB2 + AC2 = 92 + 402 = 81 + 1600 = 1681
BC2 = AB2 + AC2 = 1681 = 412
BC2 = 412 ⇒ BC = 41
∴ x = 41

(ii) From ∆ PQR, by Pythagoras theorem,
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 7
PR2 = PQ2 + QR2
342 = y2 + 302
⇒ y2 = 342 – 302
= 1156 – 900
= 256 = 162
y2 = 162 ⇒ y = 16

(iii) From ∆ XYZ, by Pythagoras theorem,
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 8
YZ2 = XY2 + XZ2
⇒ XY2 = YZ2 – XZ2
Z2 = 392 – 362
= 1521 – 1296 = 225 = 152
Z2 = 152
⇒ Z = 15

Question 5.
An isosceles triangle has equal sides each 13 cm and a base 24 cm in length. Find its height.
Solution:
In an isosceles triangle the altitude dives its base into two equal parts. Now in the figure, ∆ ABC is an isosceles triangle with AD as its height.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 9
In the figure, AD is the altitude and Δ ABD is a right triangle.
By Pythagoras theorem,
AB2 = AD2 + BD2
⇒ AD2 = AB2 – BD2
= 132 – 122 = 169 – 144 = 25
AD2 = 25 = 2
Height: AD = 5 cm

Question 6.
In the figure, find PR and QR.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 10
Solution:
In the figure ∆ PQR is a right triangle.
By Pythagoras theorem,
PR2 = PQ2 + QR2
(x + 1)2 = 72 + x2
x2 +2 × x × 1 + 12 = 49+ x2
2x + 1 = 49
2x = 49 – 1 = 48
x = \(\frac{48}{2}\) = 24
∴ PR = x + 1 = 24 + 1 = 25
QR = x = 24

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.1

Question 7.
The length and breadth of the screen of an LED – TV are 24 inches and 18 inches. Find the length of its diagonal.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 11
Solution:
The length and breadth of a LED TV form a right angled triangle with its diagonal.
Therefore by Pythagoras theorem,
AC2 = AB2 + BC2
= 242 + 182 = 576 + 324 = 900 = 302
∴ AC = 30 ⇒ The length of the diagonal is 30 inches.

Question 8.
Find the distance between the helicopter and the ship.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 12
Solution:
From the figure AS is the distance between the helicopter and the ship.
∆ APS is a right angled triangle, by Pythagoras theorem,
AS2 = AP2 + PS2
= 802 + 1502
= 6400 + 22500 = 28900 = 1702
∴ The distance between the helicopter and the ship is 170 m

Question 9.
From the figure, 1. If TA = 3 cm and OT = 6 cm, find TG.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 13
Solution:
1. From the figure, if, TA = 3 cm, OT = 6 cm
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 14
By Pythagoras theorem,
OA2 = OT2 – TA2 = 62 – 32
i.e. h2 = 36 – 9 = 27 cm.
Now, by altitude – on – hypotenuse theorem
h2 = xy
27 = x × 3
x = \(\frac{27}{3}\) = 9 cm
TG = x + 3 = 9 + 3 = 12 cm

Question 10.
If RQ = 15 cm and RP = 20 cm, find PQ, PS and SQ.
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 15
Solution:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 16
RQ = 15cm
RP = 20 cm and ∆ PQR is a right angled triangle
By Pythagoras theorem, p 20 cm
PQ2 = PR2 + RQ2 = 202 + 152
= 400 + 225 = 625 = 252
∴ PQ = 25 cm
Now by altitude – on – hypotenuse theorem,
RQ2 = q x r
152 = q x 25
q = \(\frac{225}{25}\) = 9 cm ⇒ SQ = 9 cm
PR2 = P x r
202 = P x 25
P = \(\frac{400}{25}\) = 16 cm ⇒ PS = 16 cm
Answer:

  1. PQ = 25 cm
  2. PS = 16 cm
  3. SQ = 9 cm

Objective Type Questions

Question 11.
If ∆ GUT is isosceles and right angled, then ∠TUG is …………
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 17
(a) 30°
(b) 40°
(c) 45°
(d) 55°
Answer:
(c) 45°
Hint:
∠U ∠T = 45° (∆ GUT is an isosceles given)
∴ ∠TUG = 45°

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.1

Question 12.
The hypotenuse of a right angled triangle of sides 12 cm and 16 cm is ……….
(a) 28 cm
(b)20cm
(c) 24 cm
(d)21cm
Answer:
(b) 20 cm
Hint:
Side take a = 12 cm
b = 16 cm
The hypotenuse c2 = a2 + b2 = 122 + 162
2 = 400 ⇒ c = 20 cm

Question 13.
The area of a rectangle of length 21 cm and diagonal 29 cm is ………. cm2
(a) 609
(b) 580
(c) 420
(d) 210
Answer:
(c) 420
Hint:
Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3.1 18
Length = 21 cm
Diagonal = 29 cm
By the converse of Pythagoras theorem,
AB2 + BC2 = AC2
212 + x2 = 292
x2 = 841 – 441 = 400 = 202
x = 20 cm
Now area of the rectangle = length x breadth.
i.e. AB x BC = 21 cm x 20 cm = 420 cm2

Question 14.
if the square of the hypotenuse of an isosceles right triangle is 50 cm2, the length of each side is ………..
(c) 10 cm
(a) 25 cm
(b) 5 cm
(c) 10 cm
(d) 20 cm
Answer:
(b) 5 cm
Hint:
By Pythagoras theorem
c2 = a2 + b2
In an isosceles triangle, a = b
c2 = a2 + a2 = 2a2
⇒ 2a2 = 50
a2 = 25 ⇒ a = 5cm
∴ The length of each sides a = 5cm, b = 5 cm.

Samacheer Kalvi 8th Maths Solutions Term 2 Chapter 3 Geometry Ex 3.1

Question 15.
The sides of a right angled triangle are in the ratio 5 : 12 : 13 and its perimeter is 120 units then, the sides are .
(a) 25, 36, 59
(b) 10, 24, 26
(c) 36, 39, 45
(d) 20, 48, 52
Answer:
(d) 20, 48, 52
Hint:
The sides of a right angled triangle are in the ratio 5 : 12 : 13
Take the three sides as 5a, 12a, 13a
Its perimeter is 5a + 12a + 13a = 30a
It is given that 30a = 120 units
a = 4 units
∴ The sides 5a = 5 x 4 = 20 units
12a = 12 x 4 = 48 units
13a = 13 x 4 = 52 units

Samacheer Kalvi 9th English Grammar Punctuation

You can Download Samacheer Kalvi 9th English Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 9th English Grammar Punctuation

Punctuation refers to the specific markings, signs and symbols that are used in and around sentences to give them structure and to allow for correct understanding and comprehension.

  • While writing prose or poetry, we use certain signs to mark the stages of reading. They are called punctuation marks.
  • The main purpose of the Punctuation mark is to make the meaning of a sentence clear to the reader.
  • Punctuation means the right use of different marks like Full–stop, Comma, Semicolon, Colon, Question Mark…in a written sentence.

Samacheer Kalvi 9th English Grammar Punctuation 1

Samacheer Kalvi 9th English Grammar Punctuation

Punctuation Marks

1. Full Stop

  • Full stop is used to mark the end of a Statement or an Imperative sentence.
    Ex:
    Time is Gold. (Statement)
    Get me a glass of water. (Imperative)
  • After an initial (first Letter of a person ‘s name)
    Ex:
    S. Raman
    M. Renu

2. COMMA

  • To indicate a pause while reading.
    Ex:
    God willing, we will meet again.
  • To separate words in a list. (The last two items are separated by and)
    Ex:
    Health, wealth and peace to together.
    He visited Kerala, Tamil Nadu, Gujarat and Kashmir.
  • To separate the actual words spoken, from the rest of the sentences.
    Ex:
    Mala said, “I am writing a letter.”
  • To mark off certain words like No, Yes prefixed to a sentence.
    Ex:
    Yes, I come. No, I don’t come.
  • To break up group of numbers into tens, hundreds, thousands and lakhs.
    Ex:
    1,25,500
  • After salutation in letters.
    Ex:
    Dear Sir, Dear Kannan,
  • To separate the date and month from the year.
    Ex:
    1st January, 2005 22nd June, 1969

3. SEMICOLON

  • The semicolon represents a pause greater than that indicated by the comma.
    Ex:
    Uma came quickly; she ate in a hurry she went out.
  • The comma separates individual items. A semicolon separates groups of items.
    Ex:
    In the children’s room were toys, books, balls and colour pencils; in the kitchen were pots, pans, vegetables, and fruits; and the library had books, charts and maps.

4. COLON

  • The colon shows a shorter pause than a full stop, but a longer pause than a semicolon.
    Ex:
    The three great books are: the Ramayana, the Mahabharata and the Gita.
    The days of the week are: Sunday, Monday, Tuesday, Wednesday, Thursday, Friday and Saturday.

Samacheer Kalvi 9th English Grammar Punctuation

5. APOSTROPHE

  • To indicate the omission of a letter or letters when two words are joined.
    Ex:
    I’ve → I have I’m → I am Don’t → Do not won’t → will not
  • Apostrophe is used with s– to give the meaning belongs to. (Possessiveness)
    Ex:
    Ramu’s book → The book belongs to Ramu.
  • To indicate the plural of figures and letters.
    Ex:
    5’s Your 3’s and 8’s look alike.

6. QUESTION MARK

  • To end the interrogative sentence.
    Ex:
    What is your name?
    How old are you?
    Are you interested in Maths?
  • To mark off question tag.
    Ex:
    Pass the salt, will you?
    I am not angry, am I?

7. EXCLAMATION MARK

  • After interjections.
    Ex:
    Ah! Hurrah! Alas! Oh! Hush!
  • After exclamatory phrases.
    Ex:
    Well done! Miserable man!
  • After exclamatory sentences.
    Ex:
    What a useful tree the coconut is!
    How cunning the fox is!

8. QUOTATION MARKS

  • Single quotation marks or inverted commas are generally used in British English.
    Ex:
    ‘Help! I’m drowning!’
  • In American English, double quotation marks are used.
    Ex:
    “Help! I’m drowning!”
  • To mark the exact words of a speaker without any change.
    Ex:
    Rama said to Rahim, “Where are you going?”

9. CAPITAL LETTER

  • To begin a sentence.
    Ex:
    They are playing cricket.
  • To begin each line of poetry.
    Ex:
    If you can dream and not make dreams your master.
    If you can think and not make thoughts your aim.
  • For all proper nouns and adjectives derived from them.
    Ex:
    India, Indian.
  • To begin the names and surnames of persons, rivers, countries, cities, mountains, roads, buildings, days of the week, months, books, newspapers, magazines, communities, political parties.
    Ex:
    Raj, Cauvery, India, Trichy, Everest, Grand trunk road, The Hindu, Sunday…

Samacheer Kalvi 9th English Grammar Punctuation

10. HYPHEN

  • It is used to join up words or syllables.
  • To link pairs of words used as single words or group of words.
    Ex:
    home–work, father–in–law, co–operative, two–third.

Exercises
Punctuate the following :
1. On the drive, he would tell me dont waste your time playing insane games with these kids
Answer:
On the drive he would tell me, “Don’t waste your time playing insane games with these kids.

2. “Bow, wow, wow!” wagging his tail violently.
Answer:
“Bow, wow, wow!” wagging his tail violently.

3. Steady old pal weve been through bad things before and come out safely.
Answer:
Steady, old pal! Weve been through bad things before and come out safely.

4. do you want to buy it
Answer:
‘Do you want to buy it?’

5. only three years she smiled
Answer:
‘Only three years,’ she smiled.

6. I used to climb the jackfruit tree he said opening his eyes
Answer:
I used to climb the jackfruit tree,’ he said, opening his eyes.

7. She said where did you find it
Answer:
She said, “Where did you find it?”

8. A human how could a human be a teacher
Answer:
A human? How could a human be a teacher?”

9. Oh Jim i’m scared
Answer:
Oh, Jim, I’m scared!

10. she is alive someone said
Answer:
“She is alive!” someone said.

Samacheer Kalvi 9th English Grammar Punctuation

11. Hey wait a minute, ’ pongo shouted.
Answer:
Hey! Wait a minute,’ Pongo shouted.

12. tom what on earth ails that cat
Answer:
‘Tom, what on earth ails that cat?’

13. Im a grizzly from alaska and Ive come to stay.
Answer:
“I’m a grizzly from Alaska and Ive come to stay.

Samacheer Kalvi 9th English Grammar Framing Questions

You can Download Samacheer Kalvi 9th English Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 9th English Grammar Framing Questions

The interrogative pronouns who, what, whom, whose, which and the interrogative Adverbs where, when, why and how are used to frame information questions. The structure ‘how + an adjective/adverb’ may also be used to frame questions.

Exercises
1. John is writing a letter.
Answer:
What is John’s writing?

2. She walks home from school.
Answer:
Who walks home from school?

Samacheer Kalvi 9th English Grammar Framing Questions

3. The children are sitting in the garden.
Answer:
Where are the children sitting?

4. Peter runs with his dog on Sundays.
Answer:
When does Peter run with his dog?

5. My rabbit has a cage in the garden.
Answer:
What does your rabbit have in the garden?

6. They go to work by bus.
Answer:
How do they go to work?

7. David likes cats because they are nice.
Answer:
Why does David like cats?

8. Jenny isn’t sleeping late today.
Answer:
Who isn’t sleeping late today?

9. We are going to the cinema.
Answer:
Where are we going?

10. I’m leaving now.
Answer:
When are you leaving?

11. They went to Spain.
Answer:
Where did they go?

12. He writes novels.
Answer:
What does he write?

13. Lacy likes soccer
Answer:
Who likes soccer?

Samacheer Kalvi 9th English Grammar Framing Questions

14. The girls watched a serial.
Answer:
What did the girls watch?

15. He discovered the truth.
Answer:
What did he discover?

Samacheer Kalvi 9th English Grammar Connectors

You can Download Samacheer Kalvi 9th English Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 9th English Grammar Connectors

Connectors

❖ We could go to the library or the park.
❖ He neither finished his homework nor studied for the test.
❖ I did not go out because the weather was hot.

Samacheer Kalvi 9th English Grammar Connectors

In each of the above sentences, two different ideas are expressed in one sentence. To connect the ideas, some words like or, neither…nor, because are used. These words and phrases are called Connectors.

A connector may be used to indicate the relationship between the ideas expressed in a clause or a sentence.
The following connectors can be used for different purposes.

Look at the following sentences, how connectors are used.
Samacheer Kalvi 9th English Grammar Connectors 1

  • The man has much money. However, he isn’t happy at all.
  • I like playing football. On the other hand, my brother likes playing basketball.
  • His family made a lot of effort to make their son’s lessons better, conversely, he never made any effort.
  • She spent four years studying for her law degree. Meanwhile, she continued to work at the bank.
  • You are not allowed to use your phone here. Simi Early, you have to switch it off when you are in the library.
Even ifdespite the possibility that; whether or not. Even if I had time and money, I wouldn’t travel around the world.
Whereasin contrast or comparison with the fact that; while at the same time Dinesh is very hard-working whereas his brother is lazy.
Otherwisesomething or anything else; in other circumstances. He must pass the exam, otherwise, his parents will be unhappy.
Thereforefor that reason as a result of something that has just been mentioned He was injured and therefore unable to work.
Because ofby reason of. Last year my school was closed for two weeks because of heavy rain.
So thatin order that. I’ll help her in maths so that she could pass the exam.
Even thoughdespite the fact that. She shared with him even though she had just a sandwich.
After wardsafter something that you have already mentioned I have to help my mother in garden after wards, I can go to the cinema.
Unlessexcept on the condition that. Unless it stops raining, we will not go for a walk.
Althoughdespite the fact that; even though I’ll try to help them in the garden although I have got little time.

Samacheer Kalvi 9th English Grammar Connectors

Exercises
(i) Choose the best connector.
1. you saved a lot, you wouldn’t be able to buy that bike. (So that, Even if, Therefore)
Answer:
Even if

2. your chances are small, you should try to do it. (Afterwards, Even though, Otherwise)
Answer:
Even though

3. He eats only healthy food his sister gorges herself with junk food. (therefore, because of, whereas)
Answer:
whereas

4. You should learn more, you might fail in your exams. (otherwise, although, because of)
Answer:
otherwise

Samacheer Kalvi 9th English Grammar Connectors

5. Adhira wanted to play basket ball dance Bharathanatyam. (therefore, even though, as well as)
Answer:
As well as

6. _________ he was very tired, he worked very hard. (Afterwards, So that, Although)
Answer:
Although

7. Slice this meat and _________ you can boil it for thirty minutes. (after wards, although, because of)
Answer:
after wards

8. I cooked dinner _________ my friends wouldn’t have to eat out. (otherwise, unless, so that)
Ans :
so that

9. This street is slippery _________ the snow. (because of, even though, whereas)
Answer:
because of

10. I will pick you up. ________ you can get to the station on time. (Because of, So that, Afterwards)
Answer:
So that

11. Something must be wrong; _________Anu would go to school. (so that, because of, otherwise)
Answer:
otherwise

12. _________ he is very rich, he doesn’t help the poor. (Even if, Although, Therefore)
Answer:
Although

13. _________ the weather was windy, we went for a walk. (Therefore, Otherwise, Even though)
Answer:
Even though

14. She is always helpful and friendly to mc, 1 like her very much. (therefore, whereas, even though)
Answer:
therefore

15. He must be very clever; _________ he wouldn’t have passed such a hard exam. (whereas, otherwise, unless)
Answer:
otherwise

16. _________ I have a bike. I don’t often ride it. (Therefore, Although, Unless)
Answer:
Although

17. I like horror films ________ my friend prefers comedies. (unless, whereas, therefore)
Answer:
he was

18. _________ 1 learned so much, I didn’t manage to pass my exam. (Even though., So that, Because of)
Answer:
Een though

19. You’ll be sick _________ you stop eating so many sweets. (whereas, unless, otherwise)
Answer:
unless
20. _________ we are at the bus station by seven o’clock, we will miss our bus. (Whereas, Unless, Therefore)
Answer:
Unless

Samacheer Kalvi 9th English Grammar Connectors

(ii) Complete the following with connectors.
1. After he seems quite intelligent _________ he often gets poor grades. (Nonetheless is used to connect two contrasting ideas.)
Answer:
nonetheless

2. This restaurant has some of the best chefs in the town. _________ their service is excellent.
Answer:
Moreover

3. I’ve never been to Kerala ________ having friends and relatives there.
Answer:
in spite of

4. Krishnan is a reckless driver _________ he hasn’t had any accidents.
Answer:
even so

5. My sister works ten hours a day _________ she doesn’t earn much money.
Answer:
however

6. We went out __________ the cold weather.
Answer:
despite

7. 1 tried to look happy _________ feeling ill.
Answer:
ln spite of

8. There is no more food left. _________ there is plenty of snacks.
Answer:
However

9. Wash the potatoes first, _________ you can boil them.
Answer:
After wards

10. I need to work hard _________ I can pass the exam.
Answer:
so that

11. __________ he was the best candidate, he didn’t win the elections.
Answer:
Although

12. _________ you come back from your trip, we’ll meet to discuss the problem.
Answer:
Then

13. They said that the movie was fantastic, _________ I watched it.
Answer:
so

14. _________ he was very ill, he didn’t take any medicine.
Answer:
Although

15. I don’t know ________ I can buy a pair of jeans.
Answer:
where

Samacheer Kalvi 9th English Grammar Connectors

16. She went to the shops _________ couldn’t find anything that could fit her needs.
Answer:
but

17. Everybody likes him because he is nice _________ helpful.
Answer:
and

18. _________ he was angry with her, he didn’t utter a word.
Answer:
Since

19. Keep quiet _________ go out.
Answer:
or

20. She acted as __________ she is innocent.
Answer:
if

Samacheer Kalvi 9th English Grammar Connectors

Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry Ex 4.1

Students can Download Maths Chapter 4 Geometry Ex 4.1 Questions and Answers, Notes Pdf, Samacheer Kalvi 7th Maths Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry Ex 4.1

Question 1.
Can 30°, 60° and 90° be the angles of a triangle?
Solution:
Given angles 30°, 60° and 90°
Sum of the angles = 30° + 60° + 90° = 180°
∴ The given angles form a triangle.

Question 2.
Can you draw a triangle with 25°, 65° and 80° as angles?
Solution:
Given angle 25°, 65° and 80°.
Sum of the angles = 25° + 65° + 80° = 170° ≠ 180
∴ We cannot draw a triangle with these measures.

Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry Ex 4.1

Question 3.
In each of the following triangles, find the value of x.
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 1
Solution:
(i) Let ∠G = x
By angle sum property we know that,
∠E + ∠F + ∠G = 180°
80° + 55° + x = 180°
135° + x = 180°
x = 45°

(ii) Let ∠M = x
By angle sum property of triangles we have
∠M + ∠M + ∠O = 180°
x + 96° + 22° = 180°
x + 118° = 180°
X = 180° – 118° = 620

(iii) Let ∠Z = (2x + 1)° and ∠Y = 90°
By the sum property of triangles we have
∠x + ∠y + ∠z = 180°
29° + 90° + (2x + 1)° = 180°
119° + (2x + 1)° = 180°
(2x + 1)° = 180° – 119°
2x + 1° = 61°
2x = 61° – 1°
2x = 60°
x = \(\frac{60^{\circ}}{2}\)
x = 30°

(iv) Let ∠J = x and ∠L – 3x.
By angle sum property of triangles we have
∠J + ∠K + ∠L = 180°
x + 112° + 3x = 180°
4x = 180° – 112°
x = 68°
x = \(\frac{68^{\circ}}{4}\)
x = 17°

(v) Let ∠S = 3x°
Given \(\overline{\mathrm{RS}}\) = Given \(\overline{\mathrm{RT}}\) = 4.5 cm
Given ∠S = ∠T = 3x° [∵ Angles opposite to equal sides are equal]
By angle sum property of a triangle we have,
∠R + ∠S + ∠T = 180°
72° + 3x + 3x = 180°
72° + 6x = 180°
x = \(\frac{108^{\circ}}{6}\)
x = 18°

(vi) Given ∠X = 3x; ∠Y = 2x; ∠Z = ∠4x
By angle sum property of a triangle we have
∠X + ∠Y + ∠Z = 180°
3x + 2x + 4x = 180°
∴ 9x = 180°
x = \(\frac{180^{\circ}}{9}\) = 20°

(vii) Given ∠T = (x – 4)°
∠U = 90°
∠V = (3x – 2)°
By angle sum property of a triang we have
∠T + ∠U + ∠V = 180°
(x – 4)° + 90° + (3x – 2)° = 180°
x – 4° + 90° + 3x – 2° = 180°
x + 3x + 90° – 4° – 2° = 180°
4x + 84° = 180°
4x = 180° – 84°
4x = 96°
x = \(\frac{96^{\circ}}{4}\) = 24°
x = 24°

(viii) Given ∠N = (x + 31)°
∠O = (3x – 10)°
∠P = (2x – 3)°
By angle sum property of a triangle we have
∠N + ∠O + ∠P = O
(x + 31)° + (3x – 10)° + (2x – 3)° = 180°
x + 31°+ 3x – 10° + 2x – 3° = 180°
x + 3x + 2x + 31° – 10° – 3° = 180°
6x + 18° = 180°
6x = 180° + 18°
6x = 162°
x = \(\frac{162^{\circ}}{6}\) = 27°
x = 27°

Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry Ex 4.1

Question 4.
Two line segments \(\overline{A D}\) and \(\overline{B C}\) intersect at O. Joining \(\overline{A B}\) and \(\overline{D C}\) we get two triangles, ∆AOB and ∆DOC as shown in the figure. Find the ∠A and ∠B.
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 2
Solution:
In ∆AOB and ∆DOC,
∠AOB = ∠DOC [∵ Vertically opposite angles are equal]
Let ∠AOB = ∠DOC = y
By angle sum property of a triangle we have
∠A + ∠B + ∠AOB = ∠D + ∠C + ∠DOC = 180°
3x + 2x + y = 70° + 30° + y = 180°
5x + y = 100° + y = 180°
Here 5x + y = 100° + y
5x = 100° + y – y
5x = 100°
x = \(\frac{100^{\circ}}{5}\) = 20°
∠A = 3x = 3 × 20 = 60°
∠B = 2x = 2 × 20 = 40°
∠A = 60°
∠B = 40°

Question 5.
Observe the figure and find the value of
∠A + ∠N + ∠G + ∠L + ∠E + ∠S.
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 3
Solution:
In the figure we have two triangles namely ∆AGE and ∆NLS.
By angle sum property of triangles,
Sum of angles of ∆AGE = ∠A + ∠G + ∠E = 180° …(1)
Also sum of angles of ∆NLS = ∠N + ∠L + ∠S = 180° … (2)
(1) + (2) ∠A + ∠G + ∠E + ∠N + ∠L + ∠S = 180° + 180°
i.e., ∠A + ∠N + ∠G + ∠L + ∠E + ∠S = 360°

Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry Ex 4.1

Question 6.
If the three angles of a triangle are in the ratio 3 : 5 : 4, then find them.
Solution:
Given three angles of the triangles are in the ratio 3 : 5 : 4.
Let the three angle be 3x, 5x and 4x.
By angle sum property of a triangle, we have
3x + 5x + 4x = 180°
12x = 180°
x = \(\frac{180^{\circ}}{12}\)
x = 15°
∴ The angle are 3x = 3 × 15° = 45°
5x = 5 × 15° = 75°
4x = 4 × 15° = 60°
Three angles of the triangle are 45°, 75°, 60°

Question 7.
In ∆RST, ∠S is 10° greater than ∠R and ∠T is 5° less than ∠S , find the three angles of the triangle.
Solution:
In ∆RST. Let ∠R = x.
Then given S is ∠10° greater than ∠R
∴ ∠S = x + 10°
Also given ∠T is 5° less then ∠S.
So ∠T = ∠S – 5° = (x + 10)° – 5° = x + 10° – 5°
By angle sum property of triangles, sum of three angles = 180°.
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 4
∠R + ∠S + ∠T = 180°
x + x + 10° + x + 5° = 180°
3x + 15° = 180°
3x = 180° – 15°
x = \(\frac{165^{\circ}}{3}\) = 55°
∠R = x = 55°
∠S = x + 10° = 55° + 10° = 65°
∠T = x + 5° = 55° + 5° = 60°
∴ ∠R = 55°
∠S = 65°
∠T = 60°

Question 8.
In ∆ABC , if ∠B is 3 times ∠A and ∠C is 2 times ∠A, then find the angles.
Solution:
In ABC, Let ∠A = x,
then ∠B = 3 times ∠A = 3x
∠C = 2 times ∠A = 2x
By angle sum property of a triangles,
Sum of three angles of ∆ABC =180°.
∠A + ∠B + ∠C = 180
x + 3x + 2x = 180°
x (1 + 3 + 2) = 180°
6x = 180°
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 5
x = \(\frac{180^{\circ}}{6}\) = 30°
∠A = x = 30°
∠B = 3x = 3 × 30° = 90°
∠C = 2x = 2 × 30° = 60°
∴ ∠A = 30°
∠B = 90°
∠C = 60°

Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry Ex 4.1

Question 9.
In ∆XYZ, if ∠X : ∠Z is 5 : 4 and ∠Y = 72°. Find ∠X and ∠Z.
Solution:
Given in ∆XYZ, ∠X : ∠Z = 5 : 4
Let ∠X = 5x; and ∠Z = 4x given ∠Y = 72°
By the angle sum property of triangles sum of three angles of a triangles is 180°.
∠X + ∠Y + ∠Z = 180°
5x + 72 + 4x = 180°
5x + 4x = 180° – 72°
9x = 108°
x = \(\frac{108^{\circ}}{9}\) = 12°
∠X = 5x = 5 × 12° = 60°
∠Z = 4x = 4 × 12° = 48°
∴ ∠X = 60°
∠Z = 48°

Question 10.
In a right angled triangle ABC, ∠B is right angle, ∠A is x + 1 and ∠C is 2x + 5. Find ∠A and ∠C.
Solution:
Given in ∆ABC ∠B = 90°
∠A = x + 1
∠B = 2x + 5
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 6
By angle sum property of triangles
Sum of three angles of ∆ABC = 180°
∠A + ∠B + ∠C = 180°
(x + 1) + 90° + (2x + 5) = 180°
x + 2x + 1° + 90° + 5° = 180°
3x + 96° = 180°
3x = 180° – 96° = 84°
x = \(\frac{84^{\circ}}{3}\) = 28°
∠A = x + 1 = 28 + 1 = 29
∠C = 2x + 5 = 2 (28) + 5 = 56 + 5 = 61
∴ ∠A = 29°
∠C = 61°

Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry Ex 4.1

Question 11.
In a right angled triangle MNO, ∠N = 90°, MO is extended to P. If ∠NOP = 128°, find the other two angles of ∆MNO.
Solution:
Given ∠N = 90°
MO is extended to P, the exterior angle ∠NOP = 128°
Exterior angle is equal to the sum of interior opposite angles.
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 7
∴ ∠M + ∠N = 128°
∠M + 90° = 128°
∠M = 128° – 90°
∠M = 38°
By angle sum property of triangles,
∴ ∠M + ∠N + ∠O = 180°
38° + 90° + ∠O = 180°
∠O = 180° – 128°
∠O = 52°
∴ ∠M = 38° and ∠O = 52°

Question 12.
Find the value of x in each of the given triangles.
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 8
Solution:
(i) In ∆ABC, given B = 65°,
AC is extended to L, the exterior angle at C, ∠BCL = 135°
Exterior angle is equal to the sum of opposite interior angles.
∠A + ∠B = ∠BCL
∠A + 65° = 135°
∠A = 135° – 65°
∴ ∠A = 70°
x + ∠A = 180° [∵ linear pair]
x + 70° = 180° [∵ ∠A = 70°]
x = 180° – 70°
∴ x = 110°

(ii) In ∆ABC, given B = 3x – 8°
∠XAZ = ∠BAC [∵ vertically opposite angles]
8x + 7 + ∠BAC
i.e., In ∆ABC, ∠A = 8x + 7
Exterior angle ∠XCY = 120°
Exterior angle is equal to the sum of the interior opposite angles.
∠A + ∠B = 120°
8x + 7 + 3x – 8 = 120°
8x + 3x = 120° + 8 – 7
11x = 121°
x = \(\frac{121^{\circ}}{11}\) = 11°

Question 13.
In ∆LMN, MN is extended to O. If ∠MLN = 100 – x, ∠LMN = 2x and ∠LNO = 6x – 5, find the value of x.
Solution:
Exterior angle is equal to the sum of the opposite interior angles.
∠LNO = ∠MLN + ∠LMN
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 9
6x – 5 = 100° – x + 2x
6x – 5 + x – 2x = 100°
6x + x – 2x = 100° + 5°
5x = 105°
x = \(\frac{105^{\circ}}{5}\) = 21°
x = 21°

Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry Ex 4.1

Question 14.
Using the given figure find the value of x.
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 10
Solution:
In ∆EDC, side DE is extended to B, to form the exterior angle ∠CEB = x.
We know that the exterior angle is equal to the sum of the opposite interior angles
∠CEB = ∠CDE + ∠ECD
x = 50° + 60°
x = 110°

Question 15.
Using the diagram find the value of x.
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 11
Solution:
Given triangle is an equilateral triangle as the three sides are equal. For an equilateral triangle all three angles are equal and is equal to 60° Also exterior angle is equal to sum of opposite interior angles.
x = 60° + 60°.
x = 120°

Objective Type Questions

Question 16.
The angles of a triangle are in the ratio 2:3:4. Then the angles are
(i) 20,30,40
(ii) 40, 60, 80
(iii) 80, 20, 80
(iv) 10, 15, 20
Answer:
(ii) 40, 60, 80

Question 17.
One of the angles of a triangle is 65°. If the difference of the other two angles is 45°, then the two angles are
(i) 85°, 40°
(ii) 70°, 25°
(iii) 80°, 35°
(iv) 80° , 135°
Answer:
(iii) 80°,35°

Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry Ex 4.1

Question 18.
In the given figure, AB is parallel to CD. Then the value of b is
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 12
(i) 112°
(ii) 68°
(iii) 102°
(iv) 62° A
Answer:
(ii) 68°

Question 19.
In the given figure, which of the following statement is true?
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 13
(i) x + y + z = 180°
(ii) x + y + z = a + b + c
(iii) x + y + z = 2(a + b + c)
(iv) x + y + z = 3(a + b + c)
Ans :
(iii) x + y + z = 2(a + b + c)]

Question 20.
An exterior angle of a triangle is 70° and two interior opposite angles are equal. Then measure of each of these angle will be
(i) 110°
(ii) 120°
(iii) 35°
(iv) 60°
Answer:
(iii) 35°

Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry Ex 4.1

Question 21.
In a ∆ABC, AB = AC. The value of x is _____.
Samacheer Kalvi 7th Maths Solutions Term 2 Chapter 4 Geometry 4.1 14
(i) 80°
(ii) 100°
(iii) 130°
(iv) 120°
Answer:
(iii) 130°

Question 22.
If an exterior angle of a triangle is 115° and one of the interior opposite angles is 35°, then the other two angles of the triangle are
(i) 45°, 60°
(ii) 65°, 80°
(iii) 65°, 70°
(iv) 115°, 60°
Answer:
(ii) 65°, 80°