<PRE><B>Question 935501</B>

the formula for surface area of a right cylinder is:


sa1 = 2*pi*r*h + 2*pi*r^2


double the surface area and you get:


sa2 = 2*(2*pi*r*h + 2*pi*r^2) which becomes:


sa2 = 4*pi*r*h + 4*pi*r^2


double the radius of the original formula and you get:


sa3 = 2*pi*(2*r)*h + 2*pi*(2*r)^2 which becomes:


sa3 = 2*pi*2*r*h + 2*pi*2^2*r^2 which becomes:


sa3 = 4*pi*r*h + 2*pi*4*r^2 which becomes:


sa3 = 4*pi*r*h + 8*pi*r^2.


if the surface area is doubled when you double the radius, then sa2 would be equal to sa3.


it is not.


sa2 = 4*pi*r*h + 4*pi*r^2
sa3 = 4*pi*r*h + 8*pi*r^2



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