MathDB

3

Part of 1999 India Regional Mathematical Olympiad

Problems(1)

A simple geometry

Source: Indian RMO 1999 Problem 3

10/26/2005
Let ABCDABCD be a square and M,NM,N points on sides AB,BCAB, BC respectively such that ∠MDN=45∘\angle MDN = 45^{\circ}. If RR is the midpoint of MNMN show that RP=RQRP =RQ where P,QP,Q are points of intersection of ACAC with the lines MD,NDMD, ND.
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