Because of the transversal and the parallel lines, we know that A+B=180°.
So:
5x + 20 + 9x - 92 = 180
14x - 72 = 180
14x = 180 + 72
14x = 252
x = 252/14
x = 18
A = 5x + 20
A = 5*18 + 20
A = 90 + 20 = 110
(Let’s check:
B = 9*18 - 92
B = 162 - 92
B = 70
70 + 110 = 180)
