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If X is the center of the circle, find angle A .
A: 72
B: 78
C: 95
D: 190

If X is the center of the circle, find angle A . A: 72 B: 78 C: 95 D: 190-example-1
User Indiantroy
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Arc EAB is the intercepted arc of angle BCE. The rule is that the arc is double the angle measure. So the arc measure totals 102 because 51*2 = 102. But we already have arc AB as 72, so little tiny arc EA measures 30. EC is a diameter of the circle because it goes through the center. That means that arcEABC is a semicircle and semicircles measure 180 degrees. That means that arc BC measures 180-102 which is 78 degrees. Angle A intercepts arc DCB. Arc DC measures 112 and arc BC measures 78 so the whole arc is 112+78 which is 190. That means that angle A is half of that. 190/2 is 95 degrees. Choice C.
User Dpolicastro
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