Question

(a + 30)° and (2a)° are the measures of two supplementary angles. What is the measure of each angle?

Answer 1

a + 30 + 2a = 180
∴ 3a = 180 - 30
∴ 3a = 150
∴ a = 50
∴ a + 30 = 50 + 30 = 80°
∴ 2a = 2 × 50 = 100°
∴ The measures of the angles are 80° and 100°.