Question

In an isosceles triangle, each base angle is four times its vertical angle. Find all the angles of the triangle.

Answer 1

Let vertical angle of an isosceles triangle = x

∴ Each base angle = 4x

∴ x + 4x + 4x = 180° ............(Sum of angles of a triangle)

⇒ 9x = 180°

⇒ x =`(180°)/9=20°`

∴ Vertical angle = 20°
and each of the base angle = 4x
= 4 × 20° = 80°