MathDB
right-triangle problem

Source: China south east mathematical olympiad 2006 day1 problem 2

July 4, 2013
geometrygeometric transformationreflectiongeometry unsolved

Problem Statement

In ABC\triangle ABC, ABC=90\angle ABC=90^{\circ}. Points D,GD,G lie on side ACAC. Points E,FE, F lie on segment BDBD, such that AEBDAE \perp BD and GFBDGF \perp BD. Show that if BE=EFBE=EF, then ABG=DFC\angle ABG=\angle DFC.