Confocal conics are conic sections sharing a common focus. Any two confocal central conics are orthogonal (Ogilvy 1990, p. 77).
Confocal Conics
See also
Confocal Ellipses, Confocal Ellipsoidal Coordinates, Confocal Hyperbolas, Confocal Parabolas, Confocal Quadrics, Conic Section, FocusExplore with Wolfram|Alpha
References
Ogilvy, C. S. Excursions in Geometry. New York: Dover, pp. 77-78, 1990.Wells, D. The Penguin Dictionary of Curious and Interesting Geometry. London: Penguin, pp. 39-40, 1991.Referenced on Wolfram|Alpha
Confocal ConicsCite this as:
Weisstein, Eric W. "Confocal Conics." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/ConfocalConics.html