Cyclic Quad
Source: USAMO 2008 Problem 2
May 1, 2008
geometrycircumcirclegeometric transformationhomothetygeometry solvedsymmedianAngle Chasing
Problem Statement
Let be an acute, scalene triangle, and let , , and be the midpoints of , , and , respectively. Let the perpendicular bisectors of and intersect ray in points and respectively, and let lines and intersect in point , inside of triangle . Prove that points , , , and all lie on one circle.