Prove that the perpendicular bisectors of the sides of a cyclic quadrilateral are concurrent.

Let, ABCD be a cyclic quadrilateral and O be the center of


the circle passing through A, B, C, and D.



Then,


Each of AB, BC, CD and DA being a chord of the


circle, its right bisector must pass through O.


Therefore,


The right bisectors of AB, BC, CD and DA pass through and are concurrent.


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