
Sophie S. answered 10/25/22
College Senior Majoring in Comparative Lit & Language
The answer is 72.5 degrees. Complementary angles are angles which add to 90 degrees. Therefore, you can algebraically solve this problem as follows:
(2x+20)+(2x-21) = 90
combine like terms to get 4x -1 = 90
add 1 to each side to get 4x = 91
91/4 = x
and since angle a is 2x + 27 this means it is 2(91/4) + 27 or 72.5 degrees.
Angle B is 2(91/4)-21 or 24.5 degrees, which checks out since angles A and B therefore add to 90 degrees and are complementary.