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equilateral from line of circumcenter and centroid, <A=60^o

Source: 2006 Oral Moscow Geometry Olympiad grades 8-9 p6

October 17, 2020
geometryEquilateralCircumcenterCentroid

Problem Statement

In an acute-angled triangle, one of the angles is 60o60^o. Prove that the line passing through the center of the circumcircle and the intersection point of the medians of the triangle cuts off an equilateral triangle from it.
(A. Zaslavsky)