Answer:
approx. 254.469 OR 81π
Step-by-step explanation:
We know that the area formula for circles is πr^2. We must find the radius first. The radius is half the diameter, and we know the diameter. It is 18. If we divide that by 2, we get 9, so that is our radius. We now plug it into our formula. π9^2. Using order of operations, we get 81π. That is our answer. If we want you want, you can solve that out as well. If you multiply π by 81, you will get an irrational number, and if we round to the nearest thousandth, we will get 254.469.