SOLUTION: If a cone's radius and slant height are halved, then how will the new surface area compare to the old surface area? Simplify your answer and write it as a proper fraction or as

Algebra ->  Surface-area -> SOLUTION: If a cone's radius and slant height are halved, then how will the new surface area compare to the old surface area? Simplify your answer and write it as a proper fraction or as       Log On


   

Question 978640: If a cone's radius and slant height are halved, then how will the new surface area compare to the old surface area?
Simplify your answer and write it as a proper fraction or as a whole or mixed number.
The new surface area will be _____ times the old surface area.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
If a cone's radius and slant height are halved, then how will the new surface area compare to the old surface area?
Simplify your answer and write it as a proper fraction or as a whole or mixed number.
The new surface area will be _____ times the old surface area.
:
Total surface area formula
SA+=+%28pi%2Ar%2As%29+%2B+%28pi%2Ar%5E2%29 where
r = the radius
s = the slant height
SA+=+pi%2Ar%28s+%2B+r%29
:
let the original cone be 2r and 2s, half would be just r and s
cancel pi*r, then cancel (s+r)
%28pi%2Ar%28s+%2B+r%29%29%2F%28pi%2A2r%282s%2B2r%29%29 = %281%28s+%2B+r%29%29%2F%282%282s%2B2r%29%29 = %281%28s+%2B+r%29%29%2F%284%28s%2Br%29%29 = 1%2F4 of the old surface area