WOLFRAM|DEMONSTRATIONS PROJECT

Circumcircles Intersecting at the First Fermat Point

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Let ABC be a triangle. On AB, BC, and AC draw equilateral triangles on the outside of ABC with their outside vertices named C', A', and B', respectively. Then AA', BB', and CC' and the circumcircles of the three equilateral triangles intersect at one point, the first Fermat point F.