Special right triangle : , which follows immediately from the Pythagorean theorem. Of all right triangles, the 45°–45°–90° degree triangle has the smallest ratio of the hypotenuse to the sum of the legs, namely . Of all right triangles, the 45°–45°–90° degree triangle has the greatest ratio of the altitude from the hypotenuse to the sum of the legs, namely . Triangles with these angles are the only possible right triangles that are also isosceles triangles in Euclidean geometry. However, in spherical geometry and hyperbolic geometry, there are infinitely many different shapes of right isosceles triangles. This is a triangle whose three angles
Parisa (given name) Parisa (given name) Parisā () (pronounced pə-REE-sa) is a Persian given name for girls that means 'like a fairy'. The ancient Persian name "Parysatis" () is related to this name. Two notable women with the name "Parysatis" are: Parysatis, who was the wife of Darius II (), ("Dārayavahuš"), king of the Persian Empire and Parysatis II, the youngest daughter of Artaxerxes III of Persia, who was the wife of Alexander the Great. "Pari" can be used as a diminutive of Parisa. Pari () (pronounced pər-REE) means "fairy" and is used as a name of its own right as well. Pari