document.write( "Question 253747: Please help me solve:
\n" ); document.write( "1) x²+x-72\r
\n" ); document.write( "\n" ); document.write( "2) x²-15x+156\r
\n" ); document.write( "\n" ); document.write( "3) x²-6x-16\r
\n" ); document.write( "\n" ); document.write( ",Thanks \n" ); document.write( "
Algebra.Com's Answer #186172 by richwmiller(17219)\"\" \"About 
You can put this solution on YOUR website!
x²-15x+156
\n" ); document.write( "neither 15 nor 256 are prime but because the discriminant is less than zero there are no real solutions
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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%2B-15x%2B156+=+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=%28-15%29%5E2-4%2A1%2A156=-399\".
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\n" ); document.write( " The discriminant -399 is less than zero. That means that there are no solutions among real numbers.

\n" ); document.write( " If you are a student of advanced school algebra and are aware about imaginary numbers, read on.

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\n" ); document.write( " In the field of imaginary numbers, the square root of -399 is + or - \"sqrt%28+399%29+=+19.9749843554382\".
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\n" ); document.write( " The solution is
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\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%2B-15%2Ax%2B156+%29\"
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