Equilateral triangle Equilateral triangle In geometry, an equilateral triangle is a triangle in which all three sides are equal. In the familiar Euclidean geometry, an equilateral triangle is also equiangular; that is, all three internal angles are also congruent to each other and are each 60°. It is also a regular polygon, so it is also referred to as a regular triangle. Denoting the common length of the sides of the equilateral triangle as "a", we can determine using the Pythagorean theorem that: Denoting the radius of the circumscribed circle as "R", we can determine using trigonometry that: Many of these quantities
Equilateral dimension Equilateral dimension In mathematics, the equilateral dimension of a metric space is the maximum number of points that are all at equal distances from each other. Equilateral dimension has also been called "metric dimension", but the term "metric dimension" also has many other inequivalent usages. The equilateral dimension of a "d"-dimensional Euclidean space is , and the equilateral dimension of a "d"-dimensional vector space with the Chebyshev distance (L norm) is 2. However, the equilateral dimension of a space with the Manhattan distance (L norm) is not known; Kusner's conjecture, named after Robert B. Kusner, states that it is exactly