Answer:
AOB = -8x + 68
Step-by-step explanation:
AOC = 40°
BOC = 8x - 28
Angle Addition Theorem:
AOB + BOC = AOC
AOB + (8x - 28) = 40
AOB + (8x - 28) + 28 = 40 + 28
AOB + 8x - 8x = 68 - 8x
AOB = -8x + 68
AOB + BOC = AOC
(-8x + 68) + (8x - 28) = 40
-8x + 8x + 68 - 28 =40
0x + 40 = 40
40 = 40
