document.write( "Question 37633: $\"y%5E2+%2B+8y+=+2\"$ I have tried this problem a number of times and i never get the right combination let alone the right numbers. The answers available are: a) -8.2,0.2 b)8.2,-0.2 c)0.3,7.7 d)-7.7,-0.3. The only numbers I get are 0.2, 0.3, and 0.4, which is not one of the numbers. Please help! \n" ); document.write( "

Algebra.Com's Answer #23223 by Nate(3500) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"y%5E2+%2B+8y+=+2\"$
\n" ); document.write( " $\"y%5E2+%2B+8y+-+2+=+0\"$
\n" ); document.write( "Use quadratic fomula:
\n" ); document.write( " $\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"$
\n" ); document.write( " $\"x+=+%28-8+%2B-+sqrt%28+%288%29%5E2-4%2A%281%29%2A%28-2%29+%29%29%2F%282%2A%281%29%29+\"$
\n" ); document.write( " $\"x+=+%28-8+%2B-+sqrt%28+64+%2B+8+%29%29%2F%282%29+\"$
\n" ); document.write( " $\"x+=+%28-8+%2B-+sqrt%28+72+%29%29%2F%282%29+\"$
\n" ); document.write( " $\"x+=+%28-8+%2B-+sqrt%28+72+%29%29%2F%282%29+\"$
\n" ); document.write( " $\"x+=+%28-8+%2B-+6%2Asqrt%28+2+%29%29%2F%282%29+\"$
\n" ); document.write( " $\"x+=+%28-4+%2B-+3%2Asqrt%28+2+%29%29+\"$
\n" ); document.write( "Answer is B
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Solved by pluggable solver: SOLVE quadratic equation with variable

Quadratic equation $\"ax%5E2%2Bbx%2Bc=0\"$ (in our case $\"1x%5E2%2B8x%2B-2+=+0\"$ ) 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 $\"b%5E2-4ac\"$ : $\"b%5E2-4ac=%288%29%5E2-4%2A1%2A-2=72\"$ .
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\n" ); document.write( " Discriminant d=72 is greater than zero. That means that there are two solutions: $\"+x%5B12%5D+=+%28-8%2B-sqrt%28+72+%29%29%2F2%5Ca\"$ .
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\n" ); document.write( " $\"x%5B1%5D+=+%28-%288%29%2Bsqrt%28+72+%29%29%2F2%5C1+=+0.242640687119285\"$
\n" ); document.write( " $\"x%5B2%5D+=+%28-%288%29-sqrt%28+72+%29%29%2F2%5C1+=+-8.24264068711928\"$
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\n" ); document.write( " Quadratic expression $\"1x%5E2%2B8x%2B-2\"$ can be factored:
\n" ); document.write( " $\"1x%5E2%2B8x%2B-2+=+1%28x-0.242640687119285%29%2A%28x--8.24264068711928%29\"$
\n" ); document.write( " Again, the answer is: 0.242640687119285, -8.24264068711928.\n" ); document.write( "Here's your graph:
\n" ); document.write( " $\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B8%2Ax%2B-2+%29\"$

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