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concurrent wanted, hexagon related 2017 Ecuador NMO (OMEC) 3.6

Source:

September 18, 2021
geometryhexagonconcurrencyconcurrent

Problem Statement

Let ABCDEFABCDEF be a convex hexagon with sides not parallel and tangent to a circle Γ\Gamma at the midpoints PP, QQ, RR of the sides AB, CDCD, EFEF respectively. Γ\Gamma is tangent to BCBC, DEDE and FAFA at the points X,Y,ZX, Y, Z respectively. Line ABAB intersects lines EFEF and CDCD at points MM and NN respectively. Lines MZMZ and NXNX intersect at point KK. Let r r be the line joining the center of Γ\Gamma and point KK. Prove that the intersection of PYPY and QZQZ lies on the line r r.