Nikolai Ivanov Beluhov, Ten concurrent Euler lines,
Forum Geometricorum, 9 ( 2009) 271--274.


Abstract: Let F_1 and F_2 denote the Fermat-Toricelli points of a given triangle ABC. We prove that the Euler lines of the 10 triangles with vertices chosen from A, B, C, F_1, F_2 (three at a time) are concurrent at the centroid of triangle ABC.

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