Given: m arc AB = 4x, m arc BC = 3x
m arc CD = 2x, m arc DA = 3x
Find: m∠APB
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Answer:
30°
Step-by-step explanation:
The addition of the arcs AB, BC, CD and DA is equal to 360°
4x + 3x +2x +3x = 360°
12x = 360°
x = 360°/12
x = 30°
Then:
m arc AB = 4*30° = 120°
m arc CD = 2*30° = 60°
The following relation must be satisfied:
m∠APB = 1/2*(m arc AB - m arc CD)
m∠APB = 1/2*(120° - 60°)
m∠APB = 30°