axis of perspective | homology axis

The line joining the three collinear points of intersection of the extensions of corresponding sides in perspective triangles, also called the perspective axis or homology axis. The following table summarizes the perspectrices for various pairs of named triangles. Pairs in which one triangle is inscribed in another have the line at infinity as their perspectrix and are omitted in the list below.

perspective triangles | perspector | Sondat's theorem