Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency: Congruent Triangles

Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency: Congruent Triangles

Selina Publishers Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency: Congruent Triangles

Congruency: Congruent Triangles Exercise 19 – Selina Concise Mathematics Class 7 ICSE Solutions

Question 1.
State, whether the pairs of triangles given in the following figures are congruent or not:
Selina ICSE Class 7 Maths Solutions - Congruency Congruent Triangles-ex1
Selina ICSE Class 7 Maths Solutions - Congruency Congruent Triangles-ex1.

Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 1
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 2

Question 2.
In the given figure, prove that:
∆ABD ≅ ∆ ACD
Selina ICSE 7th Class Maths Book Solutions Pdf - Congruency Congruent Triangles-ex2
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 3

Question 3.
Prove that:
(i) ∆ABC ≡∆ADC
(ii) ∠B = ∠D
(iii) AC bisects angle DCB
Selina ICSE 7th Class Maths Book Solutions Pdf - Congruency Congruent Triangles-ex3
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 4

Question 4.
Prove that:
(i) ∆ABD  ≡ ∆ACD
(ii) ∠B = ∠C
(iii) ∠ADB = ∠ADC
(iv) ∠ADB = 90°
Selina Publishers Mathematics For Class 7 Solutions - Congruency Congruent Triangles-ex4
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 5
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 6

Question 5.
In the given figure, prove that:
(i) ∆ACB ≅ ∆ECD
(ii) AB = ED
Selina Publishers Mathematics For Class 7 Solutions - Congruency Congruent Triangles-ex5
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 7

Question 6.
Prove that:
(i) ∆ ABC ≅ ∆ ADC
(ii) ∠B = ∠D
Selina Class 7 ICSE Maths Solutions - Congruency Congruent Triangles-ex6
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 8

Question 7.
In the given figure, prove that: BD = BC.
Selina Class 7 ICSE Maths Solutions - Congruency Congruent Triangles-ex7
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 9

Question 8.
In the given figure ;
∠1 = ∠2 and AB = AC. Prove that:
(i) ∠B = ∠C
(ii) BD = DC
(iii) AD is perpendicular to BC.
Selina Maths For Class 7 ICSE - Congruency Congruent Triangles-ex8
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 10

Question 9.
In the given figure prove that:
(i) PQ = RS
(ii) PS = QR
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles Q9

Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 11

Question 10.
(i) ∆ XYZ ≅ ∆ XPZ
(ii) YZ = PZ
(iii) ∠YXZ = ∠PXZ
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles Q10

Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 12

Question 11.
In the given figure, prove that:
(i) ∆ABC ≅ ∆ DCB
(ii) AC=DB
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles Q11
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 13

Question 12.
In the given figure, prove that:
(i) ∆ AOD ≅ ∆ BOC
(ii) AD = BC
(iii) ∠ADB = ∠ACB
(iv) ∆ADB ≅ ∆BCA
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles Q12
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 14

Question 13.
ABC is an equilateral triangle, AD and BE are perpendiculars to BC and AC respectively. Prove that:
(i) AD = BE
(ii)BD = CE
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles Q13
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 15

Question 14.
Use the informations given in the following figure to prove triangles ABD and CBD are congruent.
Also, find the values of x and y.
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles Q14
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 16

Question 15.
The given figure shows a triangle ABC in which AD is perpendicular to side BC and BD = CD. Prove that:
(i) ∆ABD ≅ ∆ACD
(ii) AB=AC
(iii) ∠B = ∠C
Selina Concise Mathematics Class 7 ICSE Solutions - Congruency Congruent Triangles-ex15
Solution:
Selina Concise Mathematics Class 7 ICSE Solutions Chapter 19 Congruency Congruent Triangles 17

Selina Concise Mathematics Class 7 ICSE Solutions