document.write( "Question 1062061: A rectangular room must have a perimeter of 20 feet and an area of at least 20 square feet. Describe the possible widths of the room. Round your answers to the nearest tenth of a foot \n" ); document.write( "
Algebra.Com's Answer #676848 by Alan3354(69443)\"\" \"About 
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A rectangular room must have a perimeter of 20 feet and an area of at least 20 square feet. Describe the possible widths of the room. Round your answers to the nearest tenth of a foot
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\n" ); document.write( "L + W = 10 --> W = 10 - L
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\n" ); document.write( "L*W >= 20
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\n" ); document.write( "Solve L*W = 20
\n" ); document.write( "L*(10 - L) = 20
\n" ); document.write( "-L^2 + 10L - 20 = 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%2B10x%2B-20+=+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=%2810%29%5E2-4%2A-1%2A-20=20\".
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\n" ); document.write( " Discriminant d=20 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-10%2B-sqrt%28+20+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%2810%29%2Bsqrt%28+20+%29%29%2F2%5C-1+=+2.76393202250021\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%2810%29-sqrt%28+20+%29%29%2F2%5C-1+=+7.23606797749979\"
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\n" ); document.write( " Quadratic expression \"-1x%5E2%2B10x%2B-20\" can be factored:
\n" ); document.write( " \"-1x%5E2%2B10x%2B-20+=+%28x-2.76393202250021%29%2A%28x-7.23606797749979%29\"
\n" ); document.write( " Again, the answer is: 2.76393202250021, 7.23606797749979.\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%2B10%2Ax%2B-20+%29\"

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\n" ); document.write( "L =~ 2.8 feet
\n" ); document.write( "W =~ 7.2 feet
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\n" ); document.write( "Neither L nor W can be less than 2.8 feet (to the nearest 10th)\r
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