SOLUTION: 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 sur

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Question 187227This question is from textbook Mathematics For Elementary Teachers
: 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. If you could help me on this problem it would be greatly appreciated. Thanks
This question is from textbook Mathematics For Elementary Teachers

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
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.