document.write( "Question 17699: 2x^2+7x-4=0 \n" ); document.write( "
Algebra.Com's Answer #8556 by xcentaur(357)\"\" \"About 
You can put this solution on YOUR website!
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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 \"2x%5E2%2B7x%2B-4+=+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=%287%29%5E2-4%2A2%2A-4=81\".
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\n" ); document.write( " Discriminant d=81 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-7%2B-sqrt%28+81+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%287%29%2Bsqrt%28+81+%29%29%2F2%5C2+=+0.5\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%287%29-sqrt%28+81+%29%29%2F2%5C2+=+-4\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B7x%2B-4\" can be factored:
\n" ); document.write( " \"2x%5E2%2B7x%2B-4+=+%28x-0.5%29%2A%28x--4%29\"
\n" ); document.write( " Again, the answer is: 0.5, -4.\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%2B7%2Ax%2B-4+%29\"
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