hat is the radius of a sphere with a surface area of 100πcm^2?

Question

anonymous · Answer

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find r then by canceling out pi from both sides.....it will be 5cm

anonymous · Answer

@vidushi, please use the text option if you are going to do a drawing.

displayerror · Answer

Surface area of a sphere is given by 
$$4 \pi r^2$$
Set that equal to the surface area (which you're given)
$$100 \pi = 4 \pi r^2$$
$$25 = r^2$$
$$r = \pm 5$$
Radius can only be positive, so reject the negative 5 value
$$r=5$$

anonymous · Answer

ok rrrrrr

goldphenoix · Answer

(Sphere) S.A = $$100πcm^2$$  To find the surface area of any sphere, you must use the formula: $$4\Pi r^2$$.
Since you have the surface area, you must go backward.
$$4\pi r^2 = 100\pi cm^2$$ Divide 4: $$\pi r^2 = 25 \pi cm^2$$ Square root it:
$$\pi = 5 \pi cm^2$$ Divide pi.
R= $$R= 5 CM$$

anonymous · Answer

thanks everyone

goldphenoix · Answer

No problem. :)