Configuration with three similar triangles
Source: IGO 2022 Intermediate P3
December 13, 2022
geometrysimilar triangles
Problem Statement
Let be the circumcenter of triangle . Arbitrary points and lie on the sides and , respectively. Points and lie in the same half-plane as point with respect to the line , and satisfy (in this exact order). Prove that .Proposed by Medeubek Kungozhin, Kazakhstan