MathDB

7

Part of 2002 Indonesia MO

Problems(1)

A rhombus' vertices on another rhombus' boundary

Source: INAMO 2002 - Problem 7

8/5/2011
Let ABCDABCD be a rhombus where ∠DAB=60∘\angle DAB = 60^\circ, and PP be the intersection between ACAC and BDBD. Let Q,R,SQ,R,S be three points on the boundary of ABCDABCD such that PQRSPQRS is a rhombus. Prove that exactly one of Q,R,SQ,R,S lies on one of A,B,C,DA,B,C,D.
geometryrhombusgeometry unsolved