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A circle has an area of 324╥ cm². What is the radius?

A) 18 c,
B) 36╥ cm
C) 18╥ cm
D) 36 cm
(I think It's D) I got d=²r ...
d = (2)18 ..
BUT I'M NO SURE IF THAT

User Bland
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2 Answers

5 votes
I got 18 x 18 = 324.
User Mropa
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The area of a circle has the formula A = pi * r^2. Since the area is known, we could determine the radius of the circle.

A = pi*r^2
324*pi = pi*r^2
324 = r^2
r = square root (324)
r = 18

The answer is 18 cm.
User Fvu
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