If the surface area of a cylinder is given by SA =

Mathematics

1 answer:

Mars2501 [29]2 years ago

7 0

Answer:

The height is 11/2

Step-by-step explanation:

We know SA = 30n

and r = 2

We are solving for h. So plug in our values

30n = 2n(2)^2 + 2n(2)h

Multiply and square on the right side terms

30n = 8n + 4nh

Divide everything by n

30 = 8 + 4h

Subtract 8 on both sides

22 = 4h

Divide by 4 on both sides

h = 22/4 = 11/2

Check:

30n = 2n(2)^2 + 2n(2)(11/2)

30n = 8n + 22n

30n = 30n

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