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Number 15 is very difficult :( please help

Number 15 is very difficult :( please help-example-1
User Hannah
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4.9k points

1 Answer

14 votes
Answer:

9 inches

Step-by-step explanation:

You want to know the height of a cylinder with surface area 140π square inches and radius 5 inches. When you put these values into the formula for the surface area of a cylinder, you obtain an equation that can be solved for the height.
A = 2πr(r +h)
140π = 2π(5)(5 +h) . . . substitute given values
14 = 5 +h . . . . . . . . . . . divide by 10π
9 = h . . . . . . . . . . . . . . subtract 5
The height of the cylinder is 9 inches.
User Liqun
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