Dynamic Geometry 1476: Droz-Farny Line Theorem, Triangle, Orthocenter, Perpendicular, Collinear Midpoints, Step-by-step Illustration

If two perpendicular straight lines (L1, L2) are drawn through the orthocenter (H) of a triangle ABC, they intercept a segment (A1A2, B1B2, C1C2) on each of the three side lines. The midpoints (MA, MB, MC) of the three segments are collinear.


Static Diagram of Droz-Farny Line Theorem

Problem 1476 Droz-Farny Line Theorem, Triangle, Orthocenter, Perpendicular, Collinear Midpoints, Step-by-step Illustration, iPad Apps


Poster of the Droz-Farny Line Theorem using iPad Apps

Dynamic Geometry 1476: Droz-Farny Line Theorem, Triangle, Orthocenter, Perpendicular, Collinear Midpoints, Step-by-step Illustration Using GeoGebra, iPad Apps

Classroom Resource:
Interactive step-by-step animation using GeoGebra

This step-by-step interactive illustration was created with GeoGebra.

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