Problem

Source: 2014 Sharygin Geometry Olympiad Final Round 8.2

Tags: geometry, isosceles



Let $AH_a$ and $BH_b$ be altitudes, $AL_a$ and $BL_b$ be angle bisectors of a triangle $ABC$. It is known that $H_aH_b // L_aL_b$. Is it necessarily true that $AC = BC$? (B. Frenkin)