Question

Someone please help me with equation :)

Answer 1

Should be the second one.

Explanation:

First you have to think that the entire circle is blue. So the area of the blue circle is: 3.14*11^2 = 379.94.

Then you have to look at the smaller circle. There the radius is: 3. So the area would be: 3.14*3^2 = 28.26

They are asking you to find the shaded area. So you subtract the bigger circles area with the smaller circle.

379.94 - 28.26 = 351.68 to the exact.

Answer 2

Use the formula pi r^2. You are finding the radius. Plug the numbers in.