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The area of circle B is 4 times greater than the area of circle A. If the radius of circle A is 13 meters, what is the radius of circle B?

Geometry

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The radius of circle B is 26. To get this, we first assume the area of circle A is y, and that of circle B is 4y. Since the area of a circle is ?r^2, we have the area of circle A as 3.14 * 13 *13, which is 530.66 m^2. The area of circle B is (530.66 * 4), which is 2122.64m^2. To find the radius of circle B, we divide 2122.64 by 3.14 to get 676. The square root of 676 is 26.

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first you need to find the area of circle A by multiplying 13x13x3.14. then you multiply that number (530.66) x4 which would be 2122.64/ 2=1061.32

im in 7th grade ow my brain

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Area of a circle = (pi)(radius^2). Using that formula, you can find the area of circle A. Then multiply that number by 4 to find the area of circle B. Finally, divide THAT number by pi to find its radius^2, and then square-root that number to find its radius.
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Or, perhaps an easier way to figure this out, is you could find out what 13^2 is, multiply THAT number by 4, and then find the square root of that number. I think that both methods would end up giving you the same answer, however the second one appears to be much simpler..