document.write( "Question 150815: If the length of a rectangular field is 8 feet more than double of its width. Find the dimensions of the field if its area is 540 square feet?\r
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Algebra.Com's Answer #110759 by nerdybill(7384)\"\" \"About 
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If the length of a rectangular field is 8 feet more than double of its width. Find the dimensions of the field if its area is 540 square feet?
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\n" ); document.write( "Let w = width of field
\n" ); document.write( "2w+8 = length of field
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\n" ); document.write( "w(2w+8)= 540
\n" ); document.write( "2w^2+8w= 540
\n" ); document.write( "2w^2+8w-540 = 0
\n" ); document.write( "w^2+4w-270 = 0
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\n" ); document.write( "Since you can't factor you must use the quadratic equation. Doing so yields:
\n" ); document.write( "w={14.55, -18.55}
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\n" ); document.write( "Only the positive answer would be correct. Therefore:
\n" ); document.write( "w = 14.55 feet (width)
\n" ); document.write( "2w+8 = 37.1 feet (length)
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\n" ); document.write( "Below is the quadratic solution:
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B4x%2B-270+=+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-270=1096\".
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\n" ); document.write( " Discriminant d=1096 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-4%2B-sqrt%28+1096+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%284%29%2Bsqrt%28+1096+%29%29%2F2%5C1+=+14.5529453572468\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%284%29-sqrt%28+1096+%29%29%2F2%5C1+=+-18.5529453572468\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B4x%2B-270\" can be factored:
\n" ); document.write( " \"1x%5E2%2B4x%2B-270+=+1%28x-14.5529453572468%29%2A%28x--18.5529453572468%29\"
\n" ); document.write( " Again, the answer is: 14.5529453572468, -18.5529453572468.\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-270+%29\"
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