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ratio wanted related to orthocenter, circumcenter and 5 midpoints

Source: KJMO 2011 p5

May 3, 2019
ratiogeometrycircumcirclemidpointsmidpoint

Problem Statement

In triangle ABCABC, (ABACAB \ne AC), let the orthocenter be HH, circumcenter be OO, and the midpoint of BCBC be MM. Let HMAO=DHM \cap AO = D. Let P,Q,R,SP,Q,R,S be the midpoints of AB,CD,AC,BDAB,CD,AC,BD. Let X=PQRSX = PQ\cap RS. Find AH/OXAH/OX.