document.write( "Question 622029: what is it that people divide by when they get to the second step can someone show me in this example with work and solution. \r
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\n" ); document.write( "\n" ); document.write( "By completing the square, the expression x^2-12 x +198 equals (x+A)^2+B
\n" ); document.write( "where A = and B = \n" ); document.write( "

Algebra.Com's Answer #391079 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Set expression to $\"0\"$ to find roots
\n" ); document.write( " $\"+x%5E2+-+12x+%2B+198+=+0+\"$
\n" ); document.write( "First subtract $\"+198+\"$ from both sides
\n" ); document.write( " $\"+x%5E2+-+12x+=+-198+\"$
\n" ); document.write( "To complete the square, take 1/2 of the
\n" ); document.write( "coefficient of the $\"x\"$ term, then square
\n" ); document.write( "it, then add it to both sides
\n" ); document.write( " $\"+x%5E2+-+12x+%2B+%28-12%2F2%29%5E2+=+-198+%2B+%28-12%2F2%29%5E2+\"$
\n" ); document.write( " $\"+x%5E2+-+12x+%2B+36+=+-198+%2B+36+\"$
\n" ); document.write( " $\"+%28+x+-+6+%29%5E2+=+-162+\"$
\n" ); document.write( "Add $\"+162+\"$ to both sides
\n" ); document.write( " $\"+%28+x+-+6+%29%5E2+%2B+162+=+0+\"$
\n" ); document.write( "check:
\n" ); document.write( "Does the left side = $\"+x%5E2+-+12x+%2B+198+\"$ ?
\n" ); document.write( " $\"+%28+x+-+6+%29%5E2+%2B+162+=+x%5E2+-+12x+%2B+36+%2B+162+\"$
\n" ); document.write( " $\"++x%5E2+-+12x+%2B+36+%2B+162+=+x%5E2+-+12x+%2B+198+\"$
\n" ); document.write( "OK, so
\n" ); document.write( " $\"+%28x+%2B+A%29%5E2+%2B+B+=+%28+x+-+6+%29%5E2+%2B+162+\"$
\n" ); document.write( " $\"+A+=+-6+\"$
\n" ); document.write( " $\"+B+=+162+\"$ \r
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\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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