If a circle has a diameter of 18 in, what is the area?

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.

then, the surface area of the sphere shown in the image is: 256π sq. units!

step-by-step explanation:

the lateral surface area of a sphere is 2πrh where h=2r.

then:

surface area = 4πr^2.

in this case, r=8 units ⇒ surface area = 4π(8 units)^2. = 256π sq. units!

then, the surface area of the sphere shown in the image is: 256π sq. units!

she drove 134 miles

step-by-step explanation: