Selina solutions

# Question 1

Q1) State, whether the pairs of triangles given in the following figures are congruent or not:

Solution:

In these triangles, corresponding sides are not equal. Hence these are not congruent triangles.

In the first A, third angle

= 180°-(40°+ 30°)

= 180° – 70°

= 110°

Now in these two triangles the sides and included angle of the one are equal to the corresponding sides and included angle.

Hence these are congruent triangles

(S.A.S. axiom)

In these triangles, corresponding two sides are equal but included angles are not-equal. Hence these are not congruent triangles.

In these triangles, corresponding three sides are equal.

Hence these are congruent triangles.

(S.S.S. Axiom)

V. In these right triangles, one side and diagonal of the one, are equal to the corresponding side and diagonal are equal. Hence these are congruent triangles. –

(R.H.S. Axiom)

Vi. In these triangles two sides and one angle of the one are equal to the corresponding sides and one angle of the other are equal.

Hence these are congruent triangles.

(S.S. A. Axiom).

Vii. In A ABC. AB = 2 cm, BC = 3.5 cm and ∠C = 80° and in ∆ DEF,

DE = 2 cm, DF = 3.5 cm and ∠D = 80°

From the figure we see that two corresponding sides are equal but their included angles are not equal.

Hence, these are not congruent triangles

Want to top your mathematics exam ?

Learn from an expert tutor.

Lido

Courses

Race To Space

Teachers

Syllabus

Maths | ICSE Maths | CBSE
Science | ICSE Science | CBSE
English | ICSE English | CBSE

Terms & Policies

NCERT Syllabus

Maths
Science

Selina Syllabus

Maths
Physics
Biology

Allied Syllabus

Chemistry