MathDB

51

Part of 1971 IMO Longlists

Problems(1)

Areas of triangles OKM and OLN are different [ILL 1971]

Source:

1/1/2011
Suppose that the sides ABAB and DCDC of a convex quadrilateral ABCDABCD are not parallel. On the sides BCBC and ADAD, pairs of points (M,N)(M,N) and (K,L)(K,L) are chosen such that BM=MN=NCBM=MN=NC and AK=KL=LDAK=KL=LD. Prove that the areas of triangles OKMOKM and OLNOLN are different, where OO is the intersection point of ABAB and CDCD.
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