If the trilinear polars of the polygon vertices of a triangle are distinct from the respectively opposite sides, they meet the sides in three collinear points.
Chasles's Polars Theorem
See also
Chasles's Contact Theorem, Chasles's Polar Triangle Theorem, Chasles's Theorem Collinear, Triangle, Trilinear PolarExplore with Wolfram|Alpha
References
Altshiller-Court, N. College Geometry: A Second Course in Plane Geometry for Colleges and Normal Schools, 2nd ed., rev. enl. New York: Barnes and Noble, p. 244, 1952.Johnson, R. A. Modern Geometry: An Elementary Treatise on the Geometry of the Triangle and the Circle. Boston, MA: Houghton Mifflin, p. 101, 1929.Kimberling, C. "Polar of a Point." §1.19 in "Triangle Centers and Central Triangles." Congr. Numer. 129, 1-295, 1998.Referenced on Wolfram|Alpha
Chasles's Polars TheoremCite this as:
Weisstein, Eric W. "Chasles's Polars Theorem." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/ChaslessPolarsTheorem.html