MathDB
Floating orthocenter forms an if and only if condition

Source: 2019 Baltic Way P12

November 18, 2019
geometry

Problem Statement

Let ABCABC be a triangle and HH its orthocenter. Let DD be a point lying on the segment ACAC and let EE be the point on the line BCBC such that BCDEBC\perp DE. Prove that EHBDEH\perp BD if and only if BDBD bisects AEAE.