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There exist two points P and Q in the plane of the triangle

Source:

October 7, 2010
geometrycircumcirclegeometric transformationreflectiongeometry proposed

Problem Statement

Let ABCABC be a nonequilateral triangle. Prove that there exist two points PP and QQ in the plane of the triangle, one in the interior and one in the exterior of the circumcircle of ABCABC, such that the orthogonal projections of any of these two points on the sides of the triangle are vertices of an equilateral triangle.