We have a right triangle and we need to find the length of one of its legs.
We can write the Pyhtagorean theorem as:
[tex]3^2+b^2=5^2[/tex]
Then, we can solve for b as:
[tex]\begin{gathered} 3^2+b^2=5^2 \\ 9+b^2=25 \\ b^2=25-9 \\ b^2=16 \\ b=\sqrt[]{16} \\ b=4 \end{gathered}[/tex]
Answer: the length of b is 4 units.
