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anonymous
 one year ago
Find the exact circumference of a circle with an area equal to 36 sq. in.
a. 12 pi
b. 18 pi
c. 324 pi
anonymous
 one year ago
Find the exact circumference of a circle with an area equal to 36 sq. in. a. 12 pi b. 18 pi c. 324 pi

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0How do you find the radius from this info? Or lack thereof

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1A = pi*r^2 36 = 3.14*r^2 solve for r to get r = ??? once you know the value of r, you can find the circumference C C = 2*pi*r

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0But how do you find R? Thats where Im stuck

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0the question wants the circumference function in pi... so we can get the relation

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1did you divide both sides of 36 = 3.14*r^2 by 3.14 ?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1what do you get when you do so

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Well 36/3.14 is 11.46

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1now if r^2 = 11.46, then what must r be?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1r^2 means r squared

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1for example, 5^2 = 5*5 = 25

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So multiply 11.46 by 11.46?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Wait, no. 5.73 multiplies by 5.73?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1some number, multiplied by itself, gives 11.46

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1to find this number, you take the square root of 11.46

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1it turns out that sqrt(11.46) = 3.385 roughly which means 3.385*3.385 = 11.458225, pretty close to 11.46

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So then i have 36=3.14*3.38^2?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1now use that r value to find the circumference C use C = 2*pi*r

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So two times pi times 3.38?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.12 times pi times 3.38

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1oh sry didn't see your two, nvm

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1yes you are correct

anonymous
 one year ago
Best ResponseYou've already chosen the best response.021.23 is what I got.

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1Question: does the original "36" given in the problem also have a "pi" attached to it?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1ok so that changes things a bit

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1if the area is A = 36pi, then A = pi*r^2 36pi = pi*r^2 36 = r^2 ... the pi terms cancel if r^2 = 36, then r = ??

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1yes, then you plug that into C = 2*pi*r

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1notice how each answer has a 'pi' in it so ignore the pi for now compute 2*r and then tack on 'pi' at the end

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1example: if r = 7, then 2*pi*r = 14pi

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Im still getting the same thing.

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1you should get 12pi

anonymous
 one year ago
Best ResponseYou've already chosen the best response.02 times R which is 6 means 12. Then 12*pi. The answer I'm getting is still 37.69

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.12*r = 2*6 = 12

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1you leave it as 12pi

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Thank you so much! Sorry I am so bad at this!

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1whenever you see the key term "exact" that means to leave the 'pi's as they are

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oh. Sounds good. Thank you that means a lot!

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.1you're welcome
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