# Eyeball Theorem

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The circles and with centers and do not intersect. Draw the tangents from to and from to . The chords and , shown in red, are equal in length.

Contributed by: Izidor Hafner (December 2018)

Open content licensed under CC BY-NC-SA

## Details

Let , , .

Then , .

Reference

[1] D. Wells, *The Penguin Dictionary of Curious and Interesting Geometry*, New York: Penguin Books, 1991 p. 70.

## Snapshots

## Permanent Citation