point symmetric to circumcneter of (HOA' ) lies on midline
Source: All-Russian MO 2009 Regional 11. 4
August 27, 2024
geometrymidline
Problem Statement
In an acute non-isosceles triangle , the altitude is drawn and point is the intersection point of the altitudes and and is the center of the circumscribed circle. Prove that the point symmetric to the circumcenter of triangle wrt straight line , lies on a midline of triangle .