MathDB
PA' and B'C' intersect on A-median

Source: Spain MO 2010

February 11, 2011
geometryincentergeometry proposed

Problem Statement

In a triangle ABCABC, let PP be a point on the bisector of BAC\angle BAC and let A,BA',B' and CC' be points on lines BC,CABC,CA and ABAB respectively such that PAPA' is perpendicular to BC,PBACBC,PB'\perp AC, and PCABPC'\perp AB. Prove that PAPA' and BCB'C' intersect on the median AMAM, where MM is the midpoint of BCBC.