Someone please help me with equation :)
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Answer:
Use the formula pi r^2. You are finding the radius. Plug the numbers in.
Answer:
Should be the second one.
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.