I belive it would be 12x + 12y
Answer:

Step-by-step explanation:
The formula for the surface area of a cylinder is:

And we want to solve for the height h.
First, subtract
from both sides. This yields:

Now, divide both sides by
. This yields:

And we're done!
D(t) = -4t^3 + 40t^2 + 500t = 4088
4t^3 - 40t^2 - 500t + 4088 = 0
t = 7
Therefore, the plane has flown 4088 km 7 hours after it took off.
Well, to find the perimeter we have to add all of the side lengths, so let's do that:
2x+3 +2x+3 +2x
And we know that this equals 36 so let's solve for x
2x+3+2x+3+2x = 36
6x+6 = 36
6x = 30
x = 5
So we know know that x = 5.
Now all you have to do is plug in the values of x into the lengths
2(5) + 3
= 10+3
= 13 is the length of two of the sides.
2x
= 2(5)
= 10
And 10 is the length of the last side.