SOLUTION: what is the surface area and area of the base of a cylinder if the given height is 9 cm and a volume of 144 cubic centimeter?

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Question 840473: what is the surface area and area of the base of a cylinder if the given height is 9 cm and a volume of 144 cubic centimeter?
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
r = radius of the cross section
surface area is 2%2Api%2Ar%5E2%2B9%2A%282%2Api%2Ar%29, the 9 used because it's height, one of the dimensions of the tubular part of the cylinder.
Simplify or adjust the form of the expression:
2%2Api%28r%5E2%2B9r%29
highlight_green%282pi%2Ar%28r%2B9%29%29 which might or might not be easier to use than the first form.

FINDING THE RADIUS r.
9%2Api%2Ar%5E2=144, from given and formula for volume of cylinder.
r%5E2=144%2F%289%2Api%29
r=12%2F%283%2Api%29
highlight_green%28r=4%2Fpi%29

Surface Area, 2pi%284%2Fpi%29%284%2Fpi%2B9%29
8%284%2Fpi%2B9%29
highlight%2832%2Fpi%2B72%29