# Contact Triangles of a Triangle

Requires a Wolfram Notebook System

Interact on desktop, mobile and cloud with the free Wolfram Player or other Wolfram Language products.

Extend two sides of a triangle and construct the circle tangent to those sides and the third side of the triangle. The resulting circle is called an excircle.

[more]
Contributed by: Jay Warendorff (March 2011)

After work by: Antonio Gutierrez

Open content licensed under CC BY-NC-SA

## Snapshots

## Details

The statement of the theorem is in Problem 84. Contact Triangles Areas, Incircle, Excircle.

## Permanent Citation

"Contact Triangles of a Triangle"

http://demonstrations.wolfram.com/ContactTrianglesOfATriangle/

Wolfram Demonstrations Project

Published: March 7 2011