MathDB
Interesting orthocenter configuration

Source: ARO Regional stage 2023 10.5

February 16, 2023
geometryRussia

Problem Statement

In a triangle ABCABC, let BDBD be its altitude and let HH be its orthocenter. The perpendicular bisector of of HDHD meets (BCD)(BCD) at P,QP, Q. Prove that ∠APB+∠AQB=180o\angle APB+\angle AQB=180^{o}
Back to ProblemsView on AoPS