Question

One angle of a triangle is 80° and remaining two angles are equal. Find the measure of each of the equal angles.

Answer 1

Let in ∆ABC, = 80° and ∠B = ∠C

∵∠A + ∠B +∠c = 180°

⇒ 80° +∠B + ∠B = 180°

[∵ ∠A= 80° and 2C = ∠B]

⇒ 2∠B = 180° – 80°

⇒ ∠B = ( 100/2)= 50°

Measure of each of the equal angles = 50°