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<NHP=<AHQ wanted, 2 equilateral triangles exterior to a right triangle

Source: 2017 Romania JBMO TST4 p4

May 16, 2020
Equilateralgeometryanglesequal angles

Problem Statement

Let ABCABC be a right triangle, with the right angle at AA. The altitude from AA meets BCBC at HH and MM is the midpoint of the hypotenuse [BC][BC]. On the legs, in the exterior of the triangle, equilateral triangles BAPBAP and ACQACQ are constructed. If NN is the intersection point of the lines AMAM and PQPQ, prove that the angles NHP\angle NHP and AHQ\angle AHQ are equal.
Miguel Ochoa Sanchez and Leonard Giugiuc