Geometry problem about ABC and its circumcircle
Source: Turkey Junior Math Olympiad #3 Problem
January 19, 2019
geometrycircumcircleTurkeyJunior
Problem Statement
In an acute triangle which has a circumcircle center called , there is a line that perpendiculars to line cuts and respectively on and points. There is a point called that is different from and 's junction point on . line cuts the circumcircle of on that is different from . is the symmetry point of according to line. Prove that ,,, are circular.