2007-10-07 03:47:13 · 4 answers · asked by Alan M 1 in Science & Mathematics ➔ Mathematics
surface = 86pi square feet
but surface = pi*(r^2)
that means that 86pi=pi(r^2)
as such, r=root(86)
the diameter = 2r = 2 * root(86)
I'm just hoping i didn't misunderstand anything...
2007-10-07 03:52:47 · answer #1 · answered by Santa's little helper 2 · 0⤊ 2⤋
The surface area of a sphere with diameter d is pi(d^2). So you have pi(d^2) = 86pi, so d = sqrt(86).
Why did you need help?
2007-10-07 03:52:57 · answer #2 · answered by TurtleFromQuebec 5 · 0⤊ 0⤋
Surface area sphere = 86 * 3.142 [pi] = 270.212
so 4 * 3.142 * r * r = 270.212
r * r = 270.212 / (4 * 3.142)
= 270.212 / (12.568)
r^2 = 21.5 feet
r = 4.63 feet
diameter = 9.27 feet [answer].
2007-10-07 04:19:44 · answer #3 · answered by BB 7 · 0⤊ 0⤋
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Pay closer attention in class.
If the teacher doesn't cover it, ask about it.
They are getting paid to answer this question.
It's their job.
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2007-10-07 03:51:27 · answer #4 · answered by Fun Haver 3 · 0⤊ 1⤋