Equilateral triangle a triangle with any two sides "a" and "b", and an angle "C" between them is Each angle of an equilateral triangle is 60°, so The sine of 60° is formula_50. Thus since all sides of an equilateral triangle are equal. Equilateral triangles have frequently appeared in man made constructions: 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,
Equilateral dimension equilateral dimension is the maximum number of disjoint translates that can all touch each other. For a normed vector space of dimension "d", the equilateral dimension is at most 2; that is, the L norm has the highest equilateral dimension among all normed spaces. asked whether every normed vector space of dimension "d" has equilateral dimension at least , but this remains unknown. There exist normed spaces in any dimension for which certain sets of four equilateral points cannot be extended to any larger equilateral set but these spaces may have larger equilateral sets that do not include these four