High Quality Content by WIKIPEDIA articles! In plane geometry, a splitter of a triangle is a line segment having one endpoint at one of the three vertices of the triangle and the other so located on the perimeter as to bisect the perimeter. The three splitters concur at the Nagel point of the triangle. A triangle is one of the basic shapes of geometry: a polygon with three corners or vertices and three sides or edges which are line segments. A triangle with vertices A, B, and C is denoted triangle ABC. In Euclidean geometry any three non-collinear points determine a unique triangle and a unique plane (i.e. a two-dimensional Euclidean space).