Geometry Problem 1246

Elements: Triangle, Orthocenter, Altitude, Midpoint, Perpendicular

In the figure below, H1 is the orthocenter of a triangle ABC and H2 is the orthocenter of a triangle DBE (D on AB and E on BC). M1 and M2 are the midpoints of AE and CD, respectively, Prove that H1H2 is perpendicular to M1M2.
 


Geometry Problem 1246: Triangle, Orthocenter, Altitude, Midpoint, Perpendicular