# 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.

### Orthocenter

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

## Static Diagram of the Ortholine or Steiner Line

## Step-by-step diagrams after exporting from GeoGebra

## Poster of the Ortholine or Steiner Line using iPad Apps

### Search gogeometry.com

###
Classroom Resource:

Interactive step-by-step animation using GeoGebra

This step-by-step interactive illustration was created with
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