Compute the area of the concave quadrilateral ABHC
Source: Greek National Mathematical Olympiad 2008 - P3
November 17, 2011
geometrytrigonometrygeometry unsolved
Problem Statement
A triangle with orthocenter is inscribed in a circle with center and radius , where the angles at and are non-obtuse. If the lines and meet at point such that , compute the area of the concave quadrilateral .