Question

∠A and ∠B are supplementary angles. If m ∠A=(3 x-28) ° and m∠ B=(x-4) ° , then find the measure of ∠A.

Answer 1

∠ A = 131°

Explanation:

supplementary angles sum to 180° , that is

∠ A + ∠ B = 180

3x - 28 + x - 4 = 180

4x - 32 = 180 ( add 32 to both sides )

4x = 212 ( divide both sides by 4 )

x = 53

Then

∠ A = 3x - 28 = 3(53) - 28 = 159 - 28 = 131°