Circumference: 18π cm
Area: 81π cm²
1) Since the radius is 9 cm then we can write for the Circumference the following:
[tex]\begin{gathered} C=2\cdot\pi\cdot r \\ C=2\cdot\pi\cdot(9) \\ C=18\pi \end{gathered}[/tex]2) The area is found using another formula:
[tex]\begin{gathered} C=\pi\cdot r^2 \\ C=\pi\cdot9^2 \\ C=81\pi \end{gathered}[/tex]3) Hence, the answers are:
Circumference: 18π cm
Area: 81π cm²
