orthic triangleOrthicTriangle2002-01-08 00:55:162009-02-21 08:41:01Definition\usepackage{graphicx}
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\newcommand{\mathbb}[1]{\mathbbmss{#1}}If $ABC$ is a triangle and $AD, DE, CF$ are its three \PMlinkname{heights}{BaseAndHeightOfTriangle}, then the triangle $DEF$ is called the \emph{orthic triangle} of $ABC$.
A remarkable property of orthic triangles says that the orthocenter of $ABC$ is also the incenter of the orthic triangle $DEF$. That is, the heights of $ABC$ are the angle bisectors of $DEF$.
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