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Geometry problem about ABC and its circumcircle

Source: Turkey Junior Math Olympiad #3 Problem

January 19, 2019
geometrycircumcircleTurkeyJunior

Problem Statement

In an acute ABCABC triangle which has a circumcircle center called OO, there is a line that perpendiculars to AOAO line cuts [AB][AB] and [AC][AC] respectively on DD and EE points. There is a point called KK that is different from AOAO and BCBC's junction point on [BC][BC]. AKAK line cuts the circumcircle of ADEADE on LL that is different from AA. MM is the symmetry point of AA according to DEDE line. Prove that KK,LL,MM,OO are circular.