MathDB
<A=<D, <B=<E, <C=<F if ABCDEF is convex 6-gon, <A+<C+<E=<B+<D+<F, equal sides

Source: 1953 Hungary - Kürschák Competition p3

October 10, 2022
geometryequal segmentsequal angleshexagon

Problem Statement

ABCDEFABCDEF is a convex hexagon with all its sides equal. Also A+C+E=B+D+F\angle A + \angle C + \angle E = \angle B + \angle D + \angle F. Show that A=D\angle A = \angle D, B=E\angle B = \angle E and C=F\angle C = \angle F.