document.write( "Question 266938: z^2 + 12z + 15 \n" ); document.write( "
Algebra.Com's Answer #196028 by JBarnum(2146)\"\" \"About 
You can put this solution on YOUR website!
\"z%5E2%2B12z%2B15\" A=1 B=12 C=15
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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%2B12x%2B15+=+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=%2812%29%5E2-4%2A1%2A15=84\".
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\n" ); document.write( " Discriminant d=84 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-12%2B-sqrt%28+84+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%2812%29%2Bsqrt%28+84+%29%29%2F2%5C1+=+-1.41742430504416\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%2812%29-sqrt%28+84+%29%29%2F2%5C1+=+-10.5825756949558\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B12x%2B15\" can be factored:
\n" ); document.write( " \"1x%5E2%2B12x%2B15+=+1%28x--1.41742430504416%29%2A%28x--10.5825756949558%29\"
\n" ); document.write( " Again, the answer is: -1.41742430504416, -10.5825756949558.\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%2B12%2Ax%2B15+%29\"
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