The area of a circle is 49 π cm2. Its circumference is
(a) 7 πcm (b) 14 πcm (c) 21 πcm (d) 28 πcm
The area of a circle is found using the formulaAreaofacircle=π×r2 T
So the area of your circle is 49π
49π = \pi\times r ^2 \)
solve for r; start by dividing each side by π
49=r2 take the square root of each side:
7 = r
This circle has a radius of 7.
To find the circumference of a circle, use the formula Circumference=2π×r .
Since we solved for the radius by extracting it from the area, we can find the circumference:
Circumference=2π×r [ r=7]