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.
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