Question

Find the angles of an isosceles triangle which are in the ratio 2:2:5.

Answer 1

The equal angles and the non-equal angle are in the ratio 2:2:5.
Let equal angles be 2x each, therefore non-equal angle is 5x.
Angles of a triangle = 180°
⇒ 2x + 2x + 5x = 180°
⇒ 9x = 180°
⇒ x = 20°
Therefore, 2x = 40° and 5x = 100°
angles = 40°, 40° and 100°.