The pedal triangle pT of point P with respect to triangle T is the triangle formed by the feet of the perpendiculars drawn from point P to the sides of T (or their extensions).

If the optional argument is given and is a list of three names, these three names will be assigned to the three vertices of the pedal triangle pT

For a detailed description of the pedal triangle pT, use the routine detail (i.e., detail(pT))

Note that the routine only works if the vertices of triangle T are known.

The command with(geometry,PedalTriangle) allows the use of the abbreviated form of this command.