



 
Hi Len, You have been looking at Steve's response to an art student who is constructing a truncated cone from sheet metal. Steve gets to the equation and then says to solve for r. I would first multiply both sides by r + 282 to eliminate the fraction on the left side. The equation then becomes Since the factor r + 282 cancels on the left you are left with At this point you can multiply both sides by 1728 to eliminate the fraction on the right or use your calculator to find a decimal approximation of 911/1728. I'm going to multiply both sides by 1728 to obtain
and expand the right side to get
Subtract 911 r from both sides and the equation becomes
and dividing both sides by 817
Now it's time for the calculator which yields
I hope this helps,  


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