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 Problems Visual Index 1241-1250 Open Problems All Problems Triangles Altitude Orthocenter Midpoint Perpendicular lines View or Post a solution