b=12
Step-by-step explanation:
First things first, identify the hypotenuse. That is the longest side of the triangle and the one opposite to the right angle.
Then, fill in the equation using substitution.
5 squared is 5(5) or 25
13 squared is 13(13) or 169
Now you have 25+b^2=169
Subtract 25 from 169 to get
b^2=144
Now to even out the statement and get rid of the exponent, find the square root of 144.
You will get b=12