Sandor Kiss, The orthic-of-intouch and intouch-of-orthic
triangles,
Forum Geometricorum, 6 (2006) 171--177.
Abstract: Barycentric coordinates are used to prove that the othic
of intouch and intouch of orthic triangles are homothetic. Indeed, both
triangles are homothetic to the reference triangle. Ratios and centers of
homothety are found, and certain collinearities are proved.
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