This seems really basic to everything else I see posted... hopefully I can get some help.. asap Thank you!

A circular window has an area of 10 square feet. Find the circumference of the window.

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- Dec 2nd 2008, 11:47 PMmathmomgeometry help... please!
This seems really basic to everything else I see posted... hopefully I can get some help.. asap Thank you!

A circular window has an area of 10 square feet. Find the circumference of the window. - Dec 2nd 2008, 11:51 PMChop Suey
The area of a circle is given by:

$\displaystyle A = \pi r^2$

The circumference of a circle is given by:

$\displaystyle C = 2\pi r$

Find the radius from the given area, then find the circumference. - Dec 3rd 2008, 12:16 AMmathmom
thank you.. I guess I need a little more help, cause I have that info, I am not sure how to do that part though.

I have the area at 10 ft ^2

so how do I figure the circumference with that? I guess first figure out the radius? and how do I do that?

thank you so much! really.. sorry for needing more help... hope you can help me! - Dec 3rd 2008, 12:33 AMmr fantastic
- Dec 3rd 2008, 06:49 AMmathmom
Thank you.. could you check this and see if it is correct?

r^2=10/pi

3.183098862=r^2

20=2(pi)(3.183098862)

so the cirucumference is 20? is that right? - Dec 3rd 2008, 07:30 AMChop Suey
You substituted $\displaystyle r^2$ instead of $\displaystyle r$, which is wrong.

$\displaystyle r^2 = \frac{10}{\pi}$

$\displaystyle r = \sqrt{\frac{10}{\pi}} \approx 1.78412411615$