document.write( "Question 278634: solve: you have made a quilt that is 4ft by 5 ft. you want to use the remaining 10 square feet of fabric to add a decorative border of uniform width. what should the width of the border be?
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Algebra.Com's Answer #202719 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
4*5=20 ft^2
\n" ); document.write( "(4+x)+(5+x)=30 ft^2
\n" ); document.write( "20+9x+x^2=30\r
\n" ); document.write( "\n" ); document.write( "x^2+9x-10=0
\n" ); document.write( "(x+10)*(x-1)=0
\n" ); document.write( "x=1
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\n" ); document.write( "5*6=30
\n" ); document.write( "ok
\n" ); document.write( "add one foot border to each side.
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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%2B9x%2B-10+=+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=%289%29%5E2-4%2A1%2A-10=121\".
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\n" ); document.write( " Discriminant d=121 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-9%2B-sqrt%28+121+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%289%29%2Bsqrt%28+121+%29%29%2F2%5C1+=+1\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%289%29-sqrt%28+121+%29%29%2F2%5C1+=+-10\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B9x%2B-10\" can be factored:
\n" ); document.write( " \"1x%5E2%2B9x%2B-10+=+1%28x-1%29%2A%28x--10%29\"
\n" ); document.write( " Again, the answer is: 1, -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%2B9%2Ax%2B-10+%29\"
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