Answer:
a
Step-by-step explanation:
agree that AOB + BOC = AOC, right?
AOC = 25 = (4x - 15) + (2x + 10) solve for x first
25 = 6x - 5, now add 5 to both sides
30 = 6x divide both sides by 6, so x = 5
now substitute: BOC = 2x+10 = 10 + 10 = 20
AOB = 4x - 15 = 20 - 15 = 5
