concurrent lines
Source: Ireland 1999
July 4, 2009
geometry proposedgeometry
Problem Statement
A convex hexagon satisfies AB\equal{}BC, CD\equal{}DE, EF\equal{}FA and: \angle ABC\plus{}\angle CDE\plus{}\angle EFA \equal{} 360^{\circ}. Prove that the perpendiculars from and to and respectively are concurrent.