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

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