Excenter
The center 
of an Excircle. There are three excenters for a given Triangle, denoted 
, 
,
. The Incenter 
and excenters of a Triangle are an Orthocentric System.
where
is the Circumcenter, are the excenters, and 
is the Circumradius (Johnson 1929, p. 190).Denote the Midpoints of the original Triangle 
, 
, and 
. Then the lines 
,
, and 
intersect in a point known as the Mittenpunkt.See also Centroid (Orthocentric System), Excenter-Excenter Circle, ExcentralTriangle, Excircle, Incenter, Mittenpunkt
References
Dixon, R. Mathographics. New York: Dover, pp. 58-59, 1991. Johnson, R. A. Modern Geometry: An Elementary Treatise on the Geometry of the Triangle and the Circle. Boston, MA: Houghton Mifflin, 1929.
- Mean Distribution
- Mean Run Count Per Site
- Mean Run Density
- Mean Square Error
- Mean-Value Theorem
- Measurable Function
- Measurable Set
- Measurable Space
- Measure
- Measure Algebra
- Measure Polytope
- Measure-Preserving Transformation
- Measure Space
- Measure Theory
- Mechanical Quadrature
- Mecon
- Medial Axis
- Medial Deltoidal Hexecontahedron
- Medial Disdyakis Triacontahedron
- Medial Hexagonal Hexecontahedron
- Medial Icosacronic Hexecontahedron
- Medial Inverted Pentagonal Hexecontahedron
- Medial Pentagonal Hexecontahedron
- Medial Rhombic Triacontahedron
- Medial Triambic Icosahedron