# Pairwise Tangent Circles Centered at the Vertices of a Triangle

Requires a Wolfram Notebook System

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

Requires a Wolfram Notebook System

Edit on desktop, mobile and cloud with any Wolfram Language product.

Let P, Q, and R be the points of tangency of the incircle with the sides of a triangle ABC. Draw circles with centers at A, B, and C that go through P, Q, and R as in the figure. Then those three circles are pairwise tangent.

Contributed by: Jay Warendorff (March 2011)

Open content licensed under CC BY-NC-SA

## Snapshots

## Details

See Problem 13 in N. Altshiller-Court, *College Geometry*, 2nd ed., Mineola, NY: Dover, 2007 p. 93.