equilateral triangles, 1 vertex in 1 line, concurrency wanted
Source: Sharygin 2010 Final 9.3
October 6, 2018
geometryconcurrencyconcurrentEquilateral Triangle
Problem Statement
Points lies on a line (in indicated order). Triangles , , are regular, the vertices of the first and the third triangle are oriented counterclockwise and the vertices of the second are opposite oriented. Prove that , and concur.V.A.Yasinsky