Question

If the area of a circle is 8pi, what is the length of it's diameter?
Will fan/medal:)

Answer 1

\[\Large A = \pi*r^2\]

\[\Large 8\pi = \pi*r^2\]

\[\Large r = ???\]

Answer 2

I've tried that I just can't seem to figure out the first step I need to take!

Answer 3

how do you get r^2 all by itself

Answer 4

Somehow get rid of the pi, but I'm not sure how to?

Answer 5

why not divide both sides by pi

Answer 6

I will try that

Answer 7

that will get rid of pi on both sides

because pi/pi = 1

Answer 8

after r^2 is isolated

you have to isolate r itself

Answer 9

so square root r^2?

Answer 10

square root both sides

Answer 11

I got 2.8284721=r, but the only answer choices I have are

a. 4
b. 8
c. \[2\sqrt{2}\]
d. \[4\sqrt{2}\]

Answer 12

I don't know if I have to convert to a radical.. If so, I don't know how to.

Answer 13

Simplify \[\Large \sqrt{8}\]

Answer 14

\[2\sqrt{4}?\]

Answer 15

vice versa

Answer 16

\[\Large \sqrt{8} = \sqrt{4*2} = ???\]

Answer 17

\[4\sqrt{2}\] i mixed it up on accident

Answer 18

\[\Large \sqrt{8} = \sqrt{4*2} = \sqrt{4}*\sqrt{2} = ???\]

Answer 19

\[2\sqrt{2}\]

Answer 20

That's the radius

Answer 21

We want the diameter

Answer 22

\[\Large r = 2\sqrt{2}\]

\[\Large d = ???\]

Answer 23

urggg. so its not \[4\sqrt{2}\]

Answer 24

it is, I'm getting there

Answer 25

I want to make sure you know how to get there

Answer 26

Okay, I've never been good at radicals.. Sorry!

Answer 27

that's ok, just keep practicing and you'll get better

Answer 28

Yeah I just need A LOT of practice :) But you explain things to me very well!

Answer 29

Glad some of it is starting to make sense

Answer 30

Me too, trust me.. :)