MathDB
(AN) is touches to (K,KB) and (L,LC)

Source: Oral Moscow Geometry Olympiad 2024, 10-11.6

September 3, 2024
geometry

Problem Statement

An unequal acute-angled triangle ABCABC with an orthocenter HH is given, MM is the midpoint of side BCBC. Points KK and LL lie on a line passing through HH and perpendicular to AMAM such a KBKB and LCLC perpendicular to BCBC. Point NN lies on the line HMHM, and the lines ANAN and AHAH are symmetric with respect to the line AMAM. Prove that a circle with a diameter ANAN touches two circles: centered at KK and with a radius KBKB and with a center LL and radius LCLC.