What is 5 squared plus b squared equals 13 squared?

The equation (5^2 + b^2 = 13^2) can be simplified to (25 + b^2 = 169). To find (b^2), subtract 25 from both sides, resulting in (b^2 = 144). Taking the square root gives (b = 12) or (b = -12). Thus, the values of (b) are 12 and -12.