document.write( "Question 10295: This was under the conic section of my book but I am not sure if it is a review or if it is really a conic section problem. It seems really simple but after I looked at it for a while I realized I didn't know what to do.\r
\n" ); document.write( "\n" ); document.write( "Find the dimentions of a rectangle that has the area of 10 and a dioganal length of 5.\r
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Algebra.Com's Answer #5438 by rapaljer(4671)\"\" \"About 
You can put this solution on YOUR website!
Let x = width of the rectangle
\n" ); document.write( "y = length of the rectangle
\n" ); document.write( "5 = diagonal of the rectangle\r
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\n" ); document.write( "\n" ); document.write( "By the Theorem of Pythagoras,
\n" ); document.write( "\"+x%5E2+%2B+y%5E2+=+25\" By the way, this equation would be the equation of a circle, which is probably why this problem is in your conic section section of the book!!\r
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\n" ); document.write( "\n" ); document.write( "Solve for y:
\n" ); document.write( "\"y%5E2+=+25+-+x%5E2\"
\n" ); document.write( "\"y+=+sqrt%2825+-+x%5E2%29+\"\r
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\n" ); document.write( "\n" ); document.write( "Area = xy = 10
\n" ); document.write( "\"+x%2Asqrt%2825-+x%5E2%29+=+10\"\r
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\n" ); document.write( "\n" ); document.write( "Square both sides:
\n" ); document.write( "\"x%5E2+%2A+%2825-x%5E2%29+=+100+\"\r
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\n" ); document.write( "\n" ); document.write( "Set the equation equal to zero by taking everything to the right side of the equation, in order to get the x^4 to have a positive coefficient.
\n" ); document.write( "\"25x%5E2+-+x%5E4+=+100+\"
\n" ); document.write( "\"0+=+x%5E4+-+25x%5E2+%2B+100\"\r
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\n" ); document.write( "\n" ); document.write( "It doesn't always happen, but it sure feels good when it does--that math comes out even! This does indeed factor!!\r
\n" ); document.write( "\n" ); document.write( "\"0+=+%28x%5E2+-+20%29%28x%5E2+-+5%29+\"\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2+=+20\"
\n" ); document.write( "\"x+=+0%2B-sqrt%2820%29\"
\n" ); document.write( "\"x=+2%2Asqrt%285%29+or+-2%2Asqrt%285%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2+=+5\"
\n" ); document.write( "\"x+=+sqrt%285%29+or+-sqrt%285%29+\"\r
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\n" ); document.write( "\n" ); document.write( "It turns out that if \"x+=+sqrt%285%29\", then \"y+=+2sqrt%285%29\" and if \"x=2sqrt%285%29\", then \"y+=sqrt%285%29\". So there is actually only one solution. The rectangle is \"sqrt%285%29\" by \"2sqrt%285%29\". \r
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\n" ); document.write( "\n" ); document.write( "R^2 at SCC
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