Question

Which one could be the answer A
B
C
D

Answer 1

b.

Explanation:

angle AOC = angle BOC + angle AOB

thus

85 = (2x + 10) + (4x - 15)

85 = 6x - 5

x = 15

angle BOC = 2x + 10 = 40

angle AOB = 4x - 15 = 45