IMO 2017 Shortlist G3
Let O be the ir um enter of an a ute s alene triangle ABC. Line OA interse ts the altitudes of ABC through B and C at P ...
Category: Geometry
Problem
Let O be the ir um enter of an a ute s alene triangle ABC. Line OA interse ts the altitudes of ABC through B and C at P and Q, respe tively. The altitudes meet at H. Prove that the ir um enter of triangle PQH lies on a median of triangle ABC. (Ukraine)