Answer:
x = 28
Step-by-step explanation:
Okay COB is vertical to AOB, so we know they equal the same. Right the equation this way.
3x + x + x + 12 = 152 (collect like terms)
5x + 12 = 152 (subtract 12 on each side)
5x = 140 (divide by 5 on each side)
x = 28
(PLUG IN)
3(28) + (28) + (28) + 12 = 152
84 + 28 + 28 + 12 = 152
152 = 152
