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H is the foot of the altitude on AB, such that AH=3HB

Source: Itamo 2014 - p2

November 19, 2014
symmetrygeometrycircumcirclegeometry unsolved

Problem Statement

Let ABCABC be a triangle. Let HH be the foot of the altitude from CC on ABAB. Suppose that AH=3HBAH = 3HB. Suppose in addition we are given that
(a) MM is the midpoint of ABAB; (b) NN is the midpoint of ACAC; (c) PP is a point on the opposite side of BB with respect to the line ACAC such that NP=NCNP = NC and PC=CBPC = CB.
Prove that APM=PBA\angle APM = \angle PBA.