document.write( "Question 147500: A rectangle is 4 feet longer than it is wide and its area is 60 sqft. find it's dimensions? \n" ); document.write( "
Algebra.Com's Answer #107871 by Alan3354(69443)\"\" \"About 
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L = W + 4
\n" ); document.write( "L*W = 60
\n" ); document.write( "W*(W+4) = 60
\n" ); document.write( "\"W%5E2+%2B+4W+=+60\"
\n" ); document.write( "\"W%5E2+%2B+4W+-+60+=+0\"
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Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B4x%2B-60+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%284%29%5E2-4%2A1%2A-60=256\".
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\n" ); document.write( " Discriminant d=256 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-4%2B-sqrt%28+256+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%284%29%2Bsqrt%28+256+%29%29%2F2%5C1+=+6\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%284%29-sqrt%28+256+%29%29%2F2%5C1+=+-10\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B4x%2B-60\" can be factored:
\n" ); document.write( " \"1x%5E2%2B4x%2B-60+=+%28x-6%29%2A%28x--10%29\"
\n" ); document.write( " Again, the answer is: 6, -10.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B4%2Ax%2B-60+%29\"

\n" ); document.write( "\n" ); document.write( "Since a negative width makes no sense, we go with W = 6.
\n" ); document.write( "That makes the length = 10.
\n" ); document.write( "BTW, it's means \"it is\", not \"it is dimensions\"
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