document.write( "Question 688748: One half the square of a number increased by three timesthe number is equal to 8. Find the number \n" ); document.write( "
Algebra.Com's Answer #425683 by Stitch(470)\"\" \"About 
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\"X%5E2%2F2+%2B+3X+=+8\"
\n" ); document.write( "Subtract 8 from both sides
\n" ); document.write( "\"X%5E2%2F2+%2B+3X+-8+=+0\"
\n" ); document.write( "Multiply everthing by 2
\n" ); document.write( "\"X%5E2+%2B+6X+-+16+=+0\"
\n" ); document.write( "Use the quadratic equation\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%2B6X%2B-16+=+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=%286%29%5E2-4%2A1%2A-16=100\".
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\n" ); document.write( " Discriminant d=100 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-6%2B-sqrt%28+100+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"X%5B1%5D+=+%28-%286%29%2Bsqrt%28+100+%29%29%2F2%5C1+=+2\"
\n" ); document.write( " \"X%5B2%5D+=+%28-%286%29-sqrt%28+100+%29%29%2F2%5C1+=+-8\"
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\n" ); document.write( " Quadratic expression \"1X%5E2%2B6X%2B-16\" can be factored:
\n" ); document.write( " \"1X%5E2%2B6X%2B-16+=+1%28X-2%29%2A%28X--8%29\"
\n" ); document.write( " Again, the answer is: 2, -8.\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%2B6%2Ax%2B-16+%29\"

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\n" ); document.write( "\n" ); document.write( "The two answers are: 2 & -8
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