## Elementary Algebra

The area is 36$\pi$ units squared.
The formula for the circumference of a circle is: C = 2 $\times$ $\pi$ $\times$ r. Substitute 12$\pi$ for C to obtain: 12$\pi$ = 2 $\times$ $\pi$ $\times$ r Divide both sides by 2$\pi$ 6 = r The formula for the area of a circle is $\pi$ $\times$ $r^{2}$ Substitute 6 for r to obtain: A = $\pi$ $\times$ $6^{2}$ A = 36$\pi$