Regional Olympiad - FBH 2010 Grade 11 Problem 2
Source: Regional Olympiad - Federation of Bosnia and Herzegovina 2010
September 27, 2018
geometryangle bisectorareacircumcircle
Problem Statement
Angle bisector from vertex of acute triangle intersects side in point , and circumcircle of in point (different from ). Let and be foots of perpendiculars from point to sides and . Prove that area of quadrilateral is equal to the area of triangle