I assume this is Pythagorean Theorem where the square of the hypotenuse c is equal to the sum of the squares of the other legs, a and b, of a right triangle.
c² = a² + b²
To solve for b:
b² = c² - a²
[tex] \sqrt{b ^{2} } = \sqrt{c ^{2} -a^{2} } [/tex]
Therefore to solve for b:
[tex]b = \sqrt{c ^{2}-a ^{2} } [/tex]
