9514 1404 393
Answer:
see attached
Step-by-step explanation:
To solve for b, undo what is done to b.
[tex]\displaystyle C=2\pi\sqrt{\frac{a^2+b^2}{2}}\\\\\frac{C}{2\pi}=\sqrt{\frac{a^2+b^2}{2}}\\\\\left(\frac{C}{2\pi}\right)^2=\frac{a^2+b^2}{2}\\\\\frac{C^2}{2\pi^2}=a^2+b^2\\\\\frac{C^2}{2\pi^2}-a^2=b^2\\\\\boxed{b=\sqrt{\frac{C^2}{2\pi^2}-a^2}}[/tex]
