Reference Triangle -- from Wolfram MathWorld
- ️Weisstein, Eric W.
- ️Sun Mar 02 2003
A reference triangle is a triangle relative to which trilinear coordinates, exact trilinear coordinates, derived triangle, or other objects are defined in triangle geometry (Kimberling 1998, p. 155).
For example, in the construction "take a triangle , its excentral triangle,
then its tangential triangle,"
is the reference triangle." For example, the orthic triangle is perspective with the reference
triangle, with the perspector being the orthocenter. In this context, the reference
triangle is also known as the original triangle.
The reference triangle is the polar triangle of the polar circle and Stammler hyperbola.
A reference triangle has trilinear vertex matrix
i.e., the trilinear coordinates of the -vertex are 1:0:0, the coordinates of the
-vertex are 0:1:0, and the coordinates of the
-vertex are 0:0:1.
See also
Central Triangle, Triangle Geometry, Trilinear Coordinates, Trilinear Vertex Matrix
Explore with Wolfram|Alpha
References
Kimberling, C. "Triangle Centers and Central Triangles." Congr. Numer. 129, 1-295, 1998.
Referenced on Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Reference Triangle." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/ReferenceTriangle.html