Question

Prove that triangles abc and def are congruent ​

Answer 1

Below.

Explanation:

In Δ ABC m < B = 180 - (50+70) = 60 degrees.

in Δ DEF m < D = 180- ( 60 + 70) = 50 degrees.

BC = DE ( both are 10 cm).

m < A = m < F ( both 70 and directly opposite BC and DE)

m < C = m < D (corresponding angles and both = 50 degree)

Therefore, Δ's ABC and DEF are congruent by AAS.