Dynamic Geometry 1450: Ortholine, Steiner Line

The orthocenters of the four components triangles (BCE, ABF, ADE, CDF) of a complete quadrilateral ABCDEF lie on a line called Ortholine or Steiner Line.

See solution below

Complete quadrilateral

Complete quadrilateral ABCDEF is the figure determined by four lines, no three of which are concurrent, and their six points of intersection A, B, D, C, E, and F.


The orthocenter is the intersection of the three altitudes of a triangle.

Static Diagram of the Ortholine or Steiner Line

Dynamic Geometry 1450: Ortholine, Steiner Line. Using GeoGebra

Step-by-step diagrams after exporting from GeoGebra

Step-b-step diagrams exporting prom geogebra, Dynamic Geometry 1450: Ortholine, Steiner Line.

Poster of the Ortholine or Steiner Line using iPad Apps

Poster of Ortholine or Steiner Line, Dynamic Geometry. Using iPad

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

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Geometry Problem 1450 Solution(s)