This is the write-up of Assignment #9
Brian R. Lawler
EMAT 6680

Pedal Triangles

See the Definition and Construction of a Pedal Triangle
Exploring conditions of the Pedal Triangle
Considering various loci and traces


1a. Let triangle ABC be any triangle.
  Then if P is any point in the plane, then the triangle formed by constructing perpendiculars to the sides of ABC (extended if necessary) locate three points R, S, and T that are the intersections.
  Triangle RST is the Pedal Triangle for Pedal Point P.

Use GSP to create a script for the general construction of a pedal triangle to triangle ABC where P is any point in the plane of ABC.

Click the image on the right to interact with the figure in Geometer's Sketchpad.

Click here to download a GSP script to construct your own.

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Last revised: January 2, 2001

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