If two perpendicular straight lines (L1, L2) are drawn through the orthocenter
(H) of a triangle ABC, they intercept a segment (A_{1}A_{2}, B_{1}B_{2},
C_{1}C_{2}) on each of the three side lines. The midpoints
(M_{A}, M_{B}, M_{C}) of the three segments are
collinear.

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Geometry Problems

Open Problems

Visual Index

Ten problems: 1411-1420

All Problems

Triangle

Altitude

Orthocenter

Perpendicular lines

Midpoint

Collinear Points

Classical Theorems

GeoGebra

HTML5 and Dynamic Geometry

iPad Apps

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