The reflection of the Orthocenter about the Circumcenter. This point is also the Orthocenter of the
Anticomplementary Triangle. It has Triangle Center Function

It lies on the Euler Line.

**References**

Altshiller-Court, N. ``On the de Longchamps Circle of the Triangle.'' *Amer. Math. Monthly* **33**, 368-375, 1926.

Kimberling, C. ``Central Points and Central Lines in the Plane of a Triangle.'' *Math. Mag.* **67**, 163-187, 1994.

Vandeghen, A. ``Soddy's Circles and the de Longchamps Point of a Triangle.'' *Amer. Math. Monthly* **71**, 176-179, 1964.

© 1996-9

1999-05-24