MathDB
Perpendiculars and Angle Bisectors

Source: Olimpiada de Mayo

June 4, 2012
geometryratioprojective geometryperpendicular bisectorgeometry unsolved

Problem Statement

Given Triangle ABCABC, B=2C\angle B= 2 \angle C, and A>90\angle A>90^\circ. Let MM be midpoint of BCBC. Perpendicular of ACAC at CC intersects ABAB at DD. Show AMB=DMC\angle AMB = \angle DMC
If possible, don't use projective geometry