MathDB
Triangle

Source: Greece National Olympiad 2002 , Juniors , Problem 1.

November 18, 2005
geometrytrigonometry

Problem Statement

In the exterior of an equilateral triangle ABCABC of side α\alpha we construct an isosceles right-angled triangle ACDACD with CAD=900.\angle CAD=90^0.The lines DADA and CBCB meet at point EE. (a) Find the angle DBC.\angle DBC. (b) Express the area of triangle CDECDE in terms of α.\alpha. (c) Find the length of BD.BD.