Question 187227
 A right circular cylinder has a surface are of 112 pie. If the height of the cylinder is 10, find the diameter of the base?
When trying to solve this problem I am aware of the surface area of a right circular cylinder S = 2A+Ch but I am not sure how to find the unknown diameter so that I could then find my circumference and area of the cicrle in the cylinder.
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Area = 2pi*r*h + 2pi*r^2
112pi = 2pi*r*h + 2pi*r^2 
56 = rh + r^2
r^2 + 10h - 56 = 0
(r+14)*(r-4) = 0
r = 4
dia = 8
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Notice it's pi, the Greek letter, not pie, the dessert.