Dynamic Geometry Problem 1446: The Lemoine Line

Tangents to the circumcircle of triangle ABC, at points A, B, and C, meet sides BC, AC, and BA at points E, F, and D, respectively. Then E, F, D are collinear and line DEF is called the Lemoine line of triangle ABC.

See solution below

Static Diagram of the Lemoine Line

Geometry Problem 1446: Lemoine Line. Using GeoGebra

Poster of the Lemoine Line using iPad Apps

Poster of Lemoine Line Using iPad


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Interactive step-by-step animation using GeoGebra

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Geometry Problem 1446 Solution(s)