MathDB
ABCD with equal sides (2007 Indonedia MO Province P2 q1 OSP)

Source:

December 11, 2020
geometryparallelequal segments

Problem Statement

Let ABCDABCD be a quadrilateral with AB=BC=CD=DAAB = BC = CD = DA. (a) Prove that point A must be outside of triangle BCDBCD. (b) Prove that each pair of opposite sides on ABCDABCD is always parallel.
Back to ProblemsView on AoPS