# The Center and Radius of the Nine-Point Circle

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Let ABC be a triangle with orthocenter H, circumcenter O, and circumradius . Let the nine-point circle have center N and radius .

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Contributed by: Jay Warendorff (March 2011)

Open content licensed under CC BY-NC-SA

## Snapshots

## Details

See theorem 209 in N. Altshiller-Court, *College Geometry*, Mineola, NY: Dover, 2007 p. 104.

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