MathDB
Show that two angles are equal

Source: Junior Turkish Mathematical Olympiad 2010 Problem 1

July 24, 2011
geometryrectangleratiocircumcirclepower of a pointgeometry proposed

Problem Statement

A circle that passes through the vertex AA of a rectangle ABCDABCD intersects the side ABAB at a second point EE different from B.B. A line passing through BB is tangent to this circle at a point T,T, and the circle with center BB and passing through TT intersects the side BCBC at the point F.F. Show that if CDF=BFE,\angle CDF= \angle BFE, then EDF=CDF.\angle EDF=\angle CDF.