Glenn T. Vickers, Reciprocal Jacobi triangles and the McCay cubic,
Forum Geometricorum, 15 (2015) 179--183.
Abstract. Given a triangle and a set of three angles, the celebrated geometrical theorem of Jacobi produces a new triangle in perspective with the first. If this second triangle is related to the first by another set of three angles then these two triangles are said to be reciprocal Jacobi triangles. It is shown that the locus of the perspector is then the McCay cubic.
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