document.write( "Question 770389: How do you solve 2x^2 + 2x = 5 using the quadratic formula, and is there a way to find the exact answer? \n" ); document.write( "
Algebra.Com's Answer #469501 by tommyt3rd(5050)\"\" \"About 
You can put this solution on YOUR website!
2x^2 + 2x = 5\r
\n" ); document.write( "\n" ); document.write( "2x^2 + 2x -5 = 0\r
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B2x%2B-5+=+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=%282%29%5E2-4%2A2%2A-5=44\".
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\n" ); document.write( " Discriminant d=44 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-2%2B-sqrt%28+44+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%282%29%2Bsqrt%28+44+%29%29%2F2%5C2+=+1.1583123951777\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%282%29-sqrt%28+44+%29%29%2F2%5C2+=+-2.1583123951777\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B2x%2B-5\" can be factored:
\n" ); document.write( " \"2x%5E2%2B2x%2B-5+=+2%28x-1.1583123951777%29%2A%28x--2.1583123951777%29\"
\n" ); document.write( " Again, the answer is: 1.1583123951777, -2.1583123951777.\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%2B2%2Ax%2B-5+%29\"
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