Question

∠A and ∠B are supplementary angles. The measure of ∠A is three time the measure of ∠B.

Part A: Write an equation to represent the supplementary angle relationship between ∠A and ∠B.
Part B: Use the equation to find the measures of ∠A and ∠B.

WRITER

Answer 1

Part A:
Let m∠B = x. Then m∠A = 3x. Since they are supplementary,
3x + x = 180.

Part B:
4x = 180 → x = 45.
So m∠B = 45° and m∠A = 3(45°) = 135°.