Answer:
A = 40°
B = 50°
Step-by-step explanation:
If cos A = sin B, then A + B = 90
So, 2x/3 + 20 + 2x - 10 = 90
2x + 60 + 6x - 30 = 270
8x + 30 = 270
8x = 240
x = 30
2x/3 + 20 = 60/3 + 20 = 20 + 20 = 40
2x - 10 = 2(30) - 10 = 60 - 10 = 50 or 90 - 40 = 50
