What is the area of the bottom of a pool with the radius of 9?

The area of the bottom of a circular pool can be calculated using the formula ( A = \pi r^2 ), where ( r ) is the radius. For a pool with a radius of 9, the area would be ( A = \pi (9^2) = \pi \times 81 ). Therefore, the area is ( 81\pi ) square units, which is approximately 254.47 square units when using ( \pi \approx 3.14 ).