Special right triangle triangles are used to aid in calculating common trigonometric functions, as below: The 45°–45°–90° triangle, the 30°–60°–90° triangle, and the equilateral/equiangular (60°–60°–60°) triangle are the three Möbius triangles in the plane, meaning that they tessellate the plane via reflections in their sides; see Triangle group. In plane geometry, constructing the diagonal of a square results in a triangle whose three angles are in the ratio 1 : 1 : 2, adding up to 180° or radians. Hence, the angles respectively measure 45° (), 45° (), and 90° (). The sides in this triangle are in the ratio 1 : 1
The Three Degrees album for 15 years, Two further singles were released from the album, the re-recording of "Dirty Ol' Man" and new song "Hurry Hurry". In 1996 they released a new best of album, "Best & New Hits: When Will I See You Again", which included four re-recorded hits and six new songs. A seasonal album, "Christmas With The Three Degrees", was also recorded in 1998. This album included a cover of Wham's "Last Christmas", which was released as a remixed dance single which gave the group their 15th (and final) UK top 60 single, reaching #54. Scott, Holiday and Garrison continued