Parallel Tangents to an Ellipse
Illustration showing that tangents drawn at the ends of any diameter are parallel to each other.
Keywordsellipse, oval, ellipses, ovals, conic sections, section, radius, focus, center, Parallel, foci, chords, major axis, minor axis, external point, tangents, focal chord, focal radii, tangent line
GalleriesConic Sections: Ellipses
G.A. Wentworth Plane And Solid Geometry (Boston: Ginn & Company, 1899) 438