MathDB
Geo problem

Source: Baltic Way 1995

November 29, 2010
geometry unsolvedgeometry

Problem Statement

Let MM be the midpoint of the side ACAC of a triangle ABCABC and let HH be the foot of the altitude from BB. Let PP and QQ be orthogonal projections of AA and CC on the bisector of the angle BB. Prove that the four points H,P,MH,P,M and QQ lie on the same circle.