document.write( "Question 478219: WHAT TWO NUMBERS WHEN MULTIPLIED THEIR SUM IS 120, AND WHEN ADDED THEIR SUM IS 28? \n" ); document.write( "
Algebra.Com's Answer #327660 by Alan3354(69443)\"\" \"About 
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x*y = 120
\n" ); document.write( "x + y = 28
\n" ); document.write( "y = 28-x
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\n" ); document.write( "x*(28-x) = 120
\n" ); document.write( "\"x%5E2+-28x+%2B+120+=+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%2B-28x%2B120+=+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=%28-28%29%5E2-4%2A1%2A120=304\".
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\n" ); document.write( " Discriminant d=304 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--28%2B-sqrt%28+304+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-28%29%2Bsqrt%28+304+%29%29%2F2%5C1+=+22.7177978870813\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-28%29-sqrt%28+304+%29%29%2F2%5C1+=+5.28220211291865\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B-28x%2B120\" can be factored:
\n" ); document.write( " \"1x%5E2%2B-28x%2B120+=+%28x-22.7177978870813%29%2A%28x-5.28220211291865%29\"
\n" ); document.write( " Again, the answer is: 22.7177978870813, 5.28220211291865.\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%2B-28%2Ax%2B120+%29\"

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