document.write( "Question 307123: Use the quadratic formula to solve the equation. 2y^2-2y=7 \n" ); document.write( "
Algebra.Com's Answer #219707 by Stitch(470)\"\" \"About 
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Given: \"2Y%5E2+-+2Y+=+7\"
\n" ); document.write( "Set the equation equal to zero
\n" ); document.write( "\"2Y%5E2+-+2Y+-+7+=+0\"
\n" ); document.write( "Use the quadratic equation
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ay%5E2%2Bby%2Bc=0\" (in our case \"2y%5E2%2B-2y%2B-7+=+0\") has the following solutons:
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\n" ); document.write( " \"y%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=%28-2%29%5E2-4%2A2%2A-7=60\".
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\n" ); document.write( " Discriminant d=60 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--2%2B-sqrt%28+60+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"y%5B1%5D+=+%28-%28-2%29%2Bsqrt%28+60+%29%29%2F2%5C2+=+2.43649167310371\"
\n" ); document.write( " \"y%5B2%5D+=+%28-%28-2%29-sqrt%28+60+%29%29%2F2%5C2+=+-1.43649167310371\"
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\n" ); document.write( " Quadratic expression \"2y%5E2%2B-2y%2B-7\" can be factored:
\n" ); document.write( " \"2y%5E2%2B-2y%2B-7+=+2%28y-2.43649167310371%29%2A%28y--1.43649167310371%29\"
\n" ); document.write( " Again, the answer is: 2.43649167310371, -1.43649167310371.\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%2B-2%2Ax%2B-7+%29\"
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