document.write( "Question 872939: I need help on factoring this polynomial: $\"+8x%5E2%2B2x-21+\"$ \n" ); document.write( "

Algebra.Com's Answer #526532 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"+8x%5E2%2B2x-21+\"$
\n" ); document.write( " 8(x^2 + x/4 - 2.625)
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Solved by pluggable solver: SOLVE quadratic equation with variable

Quadratic equation $\"ax%5E2%2Bbx%2Bc=0\"$ (in our case $\"1x%5E2%2B0.25x%2B-2.625+=+0\"$ ) 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 $\"b%5E2-4ac\"$ : $\"b%5E2-4ac=%280.25%29%5E2-4%2A1%2A-2.625=10.5625\"$ .
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\n" ); document.write( " Discriminant d=10.5625 is greater than zero. That means that there are two solutions: $\"+x%5B12%5D+=+%28-0.25%2B-sqrt%28+10.5625+%29%29%2F2%5Ca\"$ .
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\n" ); document.write( " $\"x%5B1%5D+=+%28-%280.25%29%2Bsqrt%28+10.5625+%29%29%2F2%5C1+=+1.5\"$
\n" ); document.write( " $\"x%5B2%5D+=+%28-%280.25%29-sqrt%28+10.5625+%29%29%2F2%5C1+=+-1.75\"$
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\n" ); document.write( " Quadratic expression $\"1x%5E2%2B0.25x%2B-2.625\"$ can be factored:
\n" ); document.write( " $\"1x%5E2%2B0.25x%2B-2.625+=+1%28x-1.5%29%2A%28x--1.75%29\"$
\n" ); document.write( " Again, the answer is: 1.5, -1.75.\n" ); document.write( "Here's your graph:
\n" ); document.write( " $\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B0.25%2Ax%2B-2.625+%29\"$

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\n" ); document.write( " 8(x - 1.5)(x +1.75) \n" ); document.write( "

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