RMM 2013 Problem 3
Source:
March 2, 2013
geometrycircumcirclegeometric transformationhomothetyreflection
Problem Statement
Let be a quadrilateral inscribed in a circle . The lines and meet at , the lines and meet at , and the diagonals and meet at . Let be the midpoint of the segment , and let be the common point of the segment and the circle . Prove that the circumcircle of the triangle and are tangent to one another.