Dynamic Geometry 1448: Simson Line
Given a triangle ABC and a point D on its circumcircle, then the feet H,F,E of the perpendiculars drawn from D to the sides (or their extensions) are collinear. The line HFE is called the Simson line of D.
Robert Simson (1687 - 1768) was a Scottish mathematician and professor of mathematics at the University of Glasgow.
Static Diagram of the Simson Line of a triangle
Poster of the Simson Line using iPad Apps
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