Question

just check..3. The formula to find the surface area of a sphere is to take the radius of the sphere and square it and multiply that amount by pi and then multiply that by 4. This is written algebraically as S=4πr2, where S is the surface area, r is the radius, and the value of π is 3.14. Rewrite the equation to solve for the radius of the sphere if you know the sphere’s surface area. Then estimate the radius of a sphere given a surface area of 500 meters2.

answer 4 pi r^2 = 500
4 * 3.14 r^2 = 500
12.56 r^2 = 500
r^2 = 500/12.56 = 39.8
take the squareroot, then
r = sqrt(39.8) =

Answer 1

hahaha ok but i got this of the internet from 2 different web sites

Answer 2

You didn't solve the equation for r as the directions specified.

Answer 3

can u help me out

Answer 4

\[S=4\pi r^2\]
1. Divide both sides by 4 pi
2. Take the square root of both sides.

Answer 5

can you write out the whole quation for me so i can solve

Answer 6

im clue less

Answer 7

Do you see the equation I posted?

Answer 8

is that it to the equation?

Answer 9

Write this on your paper:

Answer 10

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

Answer 11

ok

Answer 12

Now draw a line under the S and another line under the 4pir^2

Answer 13

ok

Answer 14

Under both lines put 4pi

Answer 15

Now it looks like this:

Answer 16

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

Answer 17

Cancel the 4pi on the right since 4pi divided by 4pi is 1

Answer 18

So now it looks like this:
\[\frac{S}{4\pi}=r^2\]

Answer 19

Now take the square root of both sides.

Answer 20

ok

Answer 21

did that

Answer 22

Now replace S with 500 and find r

Answer 23

500/12.56= 39.80 is that right