Question

Find the length of the radius of a sphere with a surface area of 64.62 km2.

Answer 1

Sphere's surface area is 4*pi*r^2 = 64.62km2.
r = radius of sphere

Answer 2

Ööh, do you know how to solve that equation for r? :)

Answer 3

\[SA=4\pi r^2\]

Answer 4

To solve that for r first divide both sides by 4pi

Answer 5

\[\frac{SA}{4\pi }= r^2\]

Answer 6

Now take the square root of both sides to find r

Answer 7

\[\sqrt{\frac{SA}{4\pi }}=r\]

Answer 8

Now replace SA with 64.62 and do the arithmetic.

Answer 9

So, I got 2.27 km. Is this correct? (:

Answer 10

yes