

Problem 538: Triangle, Perpendicular Bisector, Circumcircle, Midpoint. Level: High School, SAT Prep, College

The figure shows a triangle ABC inscribed in
a circle O. D is a point on AC, EF is the perpendicular bisector of AD
and GH is the perpendicular bisector of CD. If DN is perpendicular to FH
at M, prove that M is the midpoint of DN.







