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.

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Static Diagram of the Simson Line of a triangle

Geometry Problem 1448: Simson Line. Using GeoGebra

Poster of the Simson Line using iPad Apps

Poster of The Simson Line Dynamic Geometry. Using iPad

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Geometry Problem 1448 Solution(s)