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2019 Junior Balkan MO, Problem 3

Source: 2019 Junior Balkan MO

June 22, 2019
geometryJBMOperpendicular bisectorcircumcirclegeometry solvedBalkanJunior Balkan

Problem Statement

Triangle ABCABC is such that AB<ACAB < AC. The perpendicular bisector of side BCBC intersects lines ABAB and ACAC at points PP and QQ, respectively. Let HH be the orthocentre of triangle ABCABC, and let MM and NN be the midpoints of segments BCBC and PQPQ, respectively. Prove that lines HMHM and ANAN meet on the circumcircle of ABCABC.