please help me answer this!!!! 15 points
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Answer:
m∡AOB = 40°
Step-by-step explanation:
m∡AOC = m∡AOB + m∡BOC (given by diagram)
108 = 3x + 4 + 8x - 28 (sub.)
132 = 11x (subt. POE and simplify)
x = 12 (div. POE)
m∡AOB = 3x + 4 (sub.)
m∡AOB = 3*12 + 4 (sub.)
m∡AOB = 40° (simplify)