Equilateral triangle terms of side length "a" can be derived directly using the Pythagorean theorem or using trigonometry. The area of a triangle is half of one side "a" times the height "h" from that side: The legs of either right triangle formed by an altitude of the equilateral triangle are half of the base "a", and the hypotenuse is the side "a" of the equilateral triangle. The height of an equilateral triangle can be found using the Pythagorean theorem so that Substituting "h" into the area formula (1/2)"ah" gives the area formula for the equilateral triangle: Using trigonometry, the area of
Hyperbolic triangle In other words, the quantity in the paragraph above is supposed to be equal to 1. Trigonometric formulas for hyperbolic triangles depend on the hyperbolic functions sinh, cosh, and tanh. If "C" is a right angle then: We also have the following equations: The area of a right angled triangle is: also The instance of an omega triangle with a right angle provides the configuration to examine the angle of parallelism in the triangle. In this case angle "B" = 0, a = c = formula_18 and formula_19, resulting in formula_20. The trigonometry formulas of right triangles also give the