MathDB
Chisinau MO p68 1973 ABC equilater if AOB, BOC, COA similar

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March 15, 2021
geometryEquilateralsimilar

Problem Statement

Inside the triangle ABCABC, point OO was chosen so that the triangles AOB,BOC,COAAOB, BOC, COA turned out to be similar. Prove that triangle ABCABC is equilateral.