orthocenters lie on a fixed circle, starting with another fixed circle
Source: 2018 Oral Moscow Geometry Olympiad grades 10-11 p3
July 25, 2019
orthocenterfixedcirclegeometry
Problem Statement
A circle is fixed, point is on it and point outside the circle. The secant passing through intersects circle at points and . Prove that the orthocenters of the triangle lie on a fixed circle.