VII Lusophon Mathematical Olympiad 2017 - Problem 6
Source: VII Lusophon Mathematical Olympiad 2017 - Problem 6
July 29, 2017
geometrycircumcircle
Problem Statement
Let ABC be a scalene triangle. Consider points D, E, F on segments AB, BC, CA, respectively, such that = and =.
Show that the circumcenter of ABC lies on the circumcircle of CEF.