document.write( "Question 578879: a rug is rectangular in shape and is 2 feet longer than it is wide. if its diagonal is 18 feet, find its dimensions \n" ); document.write( "
Algebra.Com's Answer #370811 by dfrazzetto(283)\"\" \"About 
You can put this solution on YOUR website!
Form a right triangle:\r
\n" ); document.write( "\n" ); document.write( "L=w+2 \r
\n" ); document.write( "\n" ); document.write( "let a=w, b=w+2 and c=18\r
\n" ); document.write( "\n" ); document.write( "a^2+b^2=c^2\r
\n" ); document.write( "\n" ); document.write( "w^2 + (w+2)^2 = 18^2\r
\n" ); document.write( "\n" ); document.write( "w^2 + w^2 +4w + 4 = 324\r
\n" ); document.write( "\n" ); document.write( "2w^2 + 4w + 4 = 324\r
\n" ); document.write( "\n" ); document.write( "2w^2 + 4w - 320 = 0\r
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B4x%2B-320+=+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%2A2%2A-320=2576\".
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\n" ); document.write( " Discriminant d=2576 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-4%2B-sqrt%28+2576+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%284%29%2Bsqrt%28+2576+%29%29%2F2%5C2+=+11.6885775404495\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%284%29-sqrt%28+2576+%29%29%2F2%5C2+=+-13.6885775404495\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B4x%2B-320\" can be factored:
\n" ); document.write( " \"2x%5E2%2B4x%2B-320+=+2%28x-11.6885775404495%29%2A%28x--13.6885775404495%29\"
\n" ); document.write( " Again, the answer is: 11.6885775404495, -13.6885775404495.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B4%2Ax%2B-320+%29\"

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\n" ); document.write( "\n" ); document.write( "Thus it is roughly 11.69 x 13.69
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