what is the exact area of a circle with a radius of 31 cm
A.15.5cm^2
B.31cm^2
C.961cm^2
D.240.25cm^2

Question

what is the exact area of a circle with a radius of 31 cm
A.15.5cm^2
B.31cm^2
C.961cm^2
D.240.25cm^2

mathstudent55 · Answer

Do you know the formula for the area of a circle?

mathstudent55 · Answer

Use it and keep $\pi$ as $\pi$, since they want an exact answer.

anonymous · Answer

how do i do the problem though

texaschic101 · Answer

Area of a circle is : A = pi * r^2
r = 31
now just sub
A = pi * 31^2

anonymous · Answer

subtract 31 from 2 ?

kendricklamar2014 · Answer

If u do what @texaschic101 told you, the answer would be 31/2= 15.5 so A :)

geekfromthefutur · Answer

Kendrick already told u the answer lol its a because Area of a circle is : A = pi * r^2 r = 31 now just sub A = pi * 31^2

anonymous · Answer

yea i know i got it

mathstudent55 · Answer

$A = \pi r^2 = \pi \times (31~cm)^2 - \pi \times 31~cm \times 31~cm = 961\pi ~cm^2$

anonymous · Answer

whats the answer yall came out whit three differ. ones what one is it???

mathstudent55 · Answer

The answer is $961 \pi ~cm^2$.
None of the choices show pi, but it looks like C. is the correct answer because C. should read 961pi cm^2.