Circle drawn on the side of an isosceles triangle

Prove that the circle drawn on any one of the equal sides of an isosceles triangle as diameter bisects the base.

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Answer

Let $ \triangle ABC $ be isosceles. AB=AC. let O be the middle of AB and $ \mathcal{C}(O,OA) $ the circle having AB as diameter.Let M be the intersection of $ \mathcal{C}(O,OA) $ with BC. Angle AMB is right as its measure is half of 180(measure of arc(AB)). Then $ \triangle AMB=\triangle AMC $ as are right triangles and AB=AC and AM is common.
Then BM=MC as the third pair of sides.

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