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
Poster of the Droz-Farny Line Theorem using iPad Apps
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Interactive step-by-step animation using GeoGebra
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