The figure below shows a triangle ABC
so that H is the
orthocenter, BD is the internal bisector, and M is the midpoint of AC. Line EHF is perpendicular to
BD. The circumcircle of the triangle BEF cuts the circumcircle of the
triangle ABC and BD at G and N, respectively. Prove that the points G, H,
N, and M are collinear.
See also
Conformal Mapping or Transformation of Problem
1382
Geometry Problems
Ten problems: 1381-1390
Visual Index
Open Problems
All Problems
Circle
Triangle
Angle Bisector
Orthocenter
Circumcircle
Midpoint
Collinear Points
View or Post a solution