document.write( "Question 185199: 2xsqured-8=0 \n" ); document.write( "
Algebra.Com's Answer #138914 by vleith(2983)\"\" \"About 
You can put this solution on YOUR website!
\"2x%5E2+-8+=0\"
\n" ); document.write( "\"x%5E2+-+4=+0\"
\n" ); document.write( "\"x%5E2+=+4\"
\n" ); document.write( "\"x+=+sqrt%284%29\"
\n" ); document.write( "x =2 , x =-2
\n" ); document.write( "also using quadratic eqaution
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"2x%5E2%2B0x%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=%280%29%5E2-4%2A2%2A-8=64\".
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\n" ); document.write( " Discriminant d=64 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-0%2B-sqrt%28+64+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%280%29%2Bsqrt%28+64+%29%29%2F2%5C2+=+2\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%280%29-sqrt%28+64+%29%29%2F2%5C2+=+-2\"
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\n" ); document.write( " Quadratic expression \"2x%5E2%2B0x%2B-8\" can be factored:
\n" ); document.write( " \"2x%5E2%2B0x%2B-8+=+2%28x-2%29%2A%28x--2%29\"
\n" ); document.write( " Again, the answer is: 2, -2.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B0%2Ax%2B-8+%29\"
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