Exeter point

English

Construction of the Exeter point of a triangle

Etymology

Named for the Phillips Exeter Academy (in the town of Exeter, New Hampshire), where it was discovered during a computers-in-mathematics workshop in 1986.

Noun

Exeter point (plural Exeter points)

1. (geometry, given a triangle ΔABC whose medians intersect its circumcircle at {A, A’}, {B, B’} and {C, C’} and ΔDEF constructed from the tangent lines at A, B and C such that D, E and F are respectively opposite A, B and C) The point of concurrence of the rays DA’, EB’ and FC’.
   • 2015, Gerard Venema, Just the Facts 101: Foundations of Geometry, Cram101 Textbook Reviews, unnumbered page:

     It ^{[the Euler line]} passes through the centroid, the Exeter point and the center of the nine-point circle of the triangle.

Usage notes

Designated X(22) in Clark Kimberling's online Encyclopedia of Triangle Centers.

Further reading

• Exeter Point on Wolfram MathWorld