SOLUTION: the surface area of a cylinder is 180 π square inches and the height is 9 inches. Find the radius.
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-> SOLUTION: the surface area of a cylinder is 180 π square inches and the height is 9 inches. Find the radius.
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You can put this solution on YOUR website! Surface Area=2πr2+2πrh
"=2πr(r+h)
180π=2πr(r+h)
90=r2+9r
r2+9r-90=0
(r+15)(r-6)=0
r=-15 or 6
Throwing out the negative result, we get radius equals 6 in..
