Triangle their internal angles, measured here in degrees. A triangle that has two angles with the same measure also has two sides with the same length, and therefore it is an isosceles triangle. It follows that in a triangle where all angles have the same measure, all three sides have the same length, and such a triangle is therefore equilateral. Triangles are assumed to be two-dimensional plane figures, unless the context provides otherwise (see Non-planar triangles, below). In rigorous treatments, a triangle is therefore called a "2-simplex" (see also Polytope). Elementary facts about triangles were presented by Euclid in books 1–4
The Three Degrees The Three Degrees The Three Degrees is an American female vocal group, which was originally formed in 1963 in Philadelphia, Pennsylvania. Although a total of 15 women have been a member over the years, the group has always been a trio. The current line-up consists of Valerie Holiday, Helen Scott and Freddie Pool. Holiday has been a member since she first joined in 1967, while Scott has been a permanent member since 1976, having previously been in the group from 1963 to 1966. The group were particularly successful in the UK, achieving 13 Top 50 hit singles between 1974 and