document.write( "Question 66751This question is from textbook College Algebra
\n" ); document.write( ": A rectangular piece of sheet metal with an area of 1200 in^2 is to be bent into a cylindrical length of stovepipe having a volume of 600 in^3. What are the dimensions of the sheet metal?
\n" ); document.write( "I am to come up with a system of equations to solve this problem. The sides of the rectangle are labeled x and y.
\n" ); document.write( "I know that {x*y=1200 in^2}; x would be the circumference of the cylinder which would mean that {x=2(PI)r}; the volume would be {(PI)r^2(y)=600 in^3}. I just can't figure out how to show it all in terms of y and x to figure out the equation. Thanks.\r
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Algebra.Com's Answer #47403 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
You are correct in what you have done so far.
\n" ); document.write( "Let's start with the volume of the cylindical pipe.
\n" ); document.write( "\"%28pi%29r%5E2y+=+600\" Substitute r here with: \"r+=+x%2F2%28pi%29\" from \"x+=+2%28pi%29r\"
\n" ); document.write( "\"%28pi%29%28x%2F2%28pi%29%29%5E2y+=+600\" Simplify.
\n" ); document.write( "\"%28x%5E2%2F4%28pi%29%29y+=+600\" Now substitute the y here with \"y+=+1200%2Fx\" from the area, \"xy+=+1200\"
\n" ); document.write( "\"%28x%5E2%2F4%28pi%29%29%281200%2Fx%29+=+600\" Simplify.
\n" ); document.write( "\"1200x%2F4%28pi%29+=+600\" Multiply both sides by \"4%28pi%29\"
\n" ); document.write( "\"1200x+=+2400%28pi%29\" Divide both sides by 1200.
\n" ); document.write( "\"x+=+2%28pi%29\" and, from above:
\n" ); document.write( "\"y+=+1200%2Fx\"
\n" ); document.write( "\"y+=+1200%2F2%28pi%29\"
\n" ); document.write( "\"y+=+600%2F%28pi%29\"\r
\n" ); document.write( "\n" ); document.write( "The dimensions of the rectangular metal sheet are:
\n" ); document.write( "\"2%28pi%29\" by \"600%2F%28pi%29\" inches. or...using \"%28pi%29+=+3.14\" as an approximation:
\n" ); document.write( "\"2%283.14%29\" by \"600%2F3.14\" or 6.28 by 191.08 inches.
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