MathDB
Classical triangle geometry

Source: Kazakhstan international contest 2006, Problem 2

January 22, 2006
geometryparallelogramanalytic geometryfunctiontrigonometrytrapezoidratio

Problem Statement

Let ABC ABC be a triangle and K K and L L be two points on (AB) (AB), (AC) (AC) such that BK \equal{} CL and let P \equal{} CK\cap BL. Let the parallel through P P to the interior angle bisector of BAC \angle BAC intersect AC AC in M M. Prove that CM \equal{} AB.