Enter the hypotenuse and the length of the known side into the Reverse Hypotenuse Calculator. The calculator will evaluate and display the length of the missing side.

Reverse Hypotenuse Formula

The following formula is used to calculate the Reverse Hypotenuse. 

S2 = SQRT( H^2-S1^2)

  • Where S2 is the length of the unknown side
  • H is the hypotenuse 
  • S1 is the length of the known side 

How to Calculate Reverse Hypotenuse?

The following example problems outline how to calculate Reverse Hypotenuse.

Example Problem #1:

  1. First, determine the hypotenuse. 
    • The hypotenuse is given as: 50.
  2. Next, determine the length of the known side. 
    • The length of the known side is provided as: 20.
  3. Finally, calculate the Reverse Hypotenuse using the equation above: 

S2 = SQRT( H^2-S1^2)

The values given above are inserted into the equation below and the solution is calculated:

S2 = sqrt( 50^2-20^2) = 45.825

Example Problem #2: 

For this problem, the variables required are provided below:

hypotenuse = 30

length of known side = 10

Test your knowledge using the equation and check your answer with the calculator above.

S2 = SQRT( H^2-S1^2) = ?