A Cyclic Quadrilateral Concurrency
A Cyclic Quadrilateral Concurrency
Let ABCD be a cyclic quadrilateral with circumcenter O. Let the diagonals AC and BD intersect at E. Let P be a point inside the quadrilateral and let , , , be the circumcenters of ABP, BCP, CDP and DAP. Then , , and OE are concurrent.
O
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O
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O
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O
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O
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O
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O
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O
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Drag the purple points A, B, C, or D to change the figure.