document.write( "Question 111713: please help me to solve this equation \"x%5E2-4x-8=0\" \n" ); document.write( "
Algebra.Com's Answer #81497 by MathLover1(20849)\"\" \"About 
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Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"1x%5E2%2B-4x%2B-8+=+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=%28-4%29%5E2-4%2A1%2A-8=48\".
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\n" ); document.write( " Discriminant d=48 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28--4%2B-sqrt%28+48+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28-4%29%2Bsqrt%28+48+%29%29%2F2%5C1+=+5.46410161513775\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28-4%29-sqrt%28+48+%29%29%2F2%5C1+=+-1.46410161513775\"
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\n" ); document.write( " Quadratic expression \"1x%5E2%2B-4x%2B-8\" can be factored:
\n" ); document.write( " \"1x%5E2%2B-4x%2B-8+=+%28x-5.46410161513775%29%2A%28x--1.46410161513775%29\"
\n" ); document.write( " Again, the answer is: 5.46410161513775, -1.46410161513775.\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-4%2Ax%2B-8+%29\"

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