A Right Triangle is a triangle in which one angle is 90° (shown as Φ in the figure below).

To solve a triangle means to find, from the known (given) parts, the values of the remaining parts.

A Right Triangle is determined by:

• Two of its sides (x, y in the figure below)
• One of its sides and the hypotenuse (x or y, and h in the figure below)
• One side (x or y in the figure below) and one of its acute angles (θ or ß in the figure below).

Formulas used in this site to compute the solution to a right triangle (refer to the figure below):

• h²   =   x²+y²
• 90°  =  θ°+ß°  (Note: 90° is Φ° on the figure below)
• h²    =   x²+y²   -  [2    ×    x    ×    y    ×    (Cosine Φ°)]
  
  
• Angle θ°  =  arctangent (tangent θ)  ×  (180 / π)
• Angle ß°  =  arctangent (tangent ß)  ×  (180 / π)
• Angle Φ°  =  90°