document.write( "Question 752480: F(x)=x^2-8x-10 \n" ); document.write( "
Algebra.Com's Answer #457752 by FrankM(1040)\"\" \"About 
You can put this solution on YOUR website!
Using the quadratic solver:\r
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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-8x%2B-10+=+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=%28-8%29%5E2-4%2A1%2A-10=104\".
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\n" ); document.write( " Discriminant d=104 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--8%2B-sqrt%28+104+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-8%29%2Bsqrt%28+104+%29%29%2F2%5C1+=+9.09901951359278\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-8%29-sqrt%28+104+%29%29%2F2%5C1+=+-1.09901951359278\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B-8x%2B-10\" can be factored:
\n" ); document.write( " \"1x%5E2%2B-8x%2B-10+=+1%28x-9.09901951359278%29%2A%28x--1.09901951359278%29\"
\n" ); document.write( " Again, the answer is: 9.09901951359278, -1.09901951359278.\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-8%2Ax%2B-10+%29\"

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\n" ); document.write( "\n" ); document.write( "The key thing to note is the answer is not integers, it's two irrational numbers. So the equation cannot be factored. \n" ); document.write( "
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