document.write( "Question 252147: Show that 2x^2-12x+23 is equal to 2(x+3)^2+5 \n" ); document.write( "
Algebra.Com's Answer #183928 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
I think you made a typo. The problem should be \"Show that 2x^2-12x+23 is equal to 2(x-3)^2+5\"\r
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2-12x%2B23\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%5E2-6x%2B23%2F2%29\" Factor out the \"x%5E2\" coefficient \"2\". This step is very important: the \"x%5E2\" coefficient must be equal to 1.\r
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\n" ); document.write( "\n" ); document.write( "Take half of the \"x\" coefficient \"-6\" to get \"-3\". In other words, \"%281%2F2%29%28-6%29=-3\".\r
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\n" ); document.write( "\n" ); document.write( "Now square \"-3\" to get \"9\". In other words, \"%28-3%29%5E2=%28-3%29%28-3%29=9\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%5E2-6x%2Bhighlight%289-9%29%2B23%2F2%29\" Now add and subtract \"9\" inside the parenthesis. Make sure to place this after the \"x\" term. Notice how \"9-9=0\". So the expression is not changed.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28%28x%5E2-6x%2B9%29-9%2B23%2F2%29\" Group the first three terms.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28%28x-3%29%5E2-9%2B23%2F2%29\" Factor \"x%5E2-6x%2B9\" to get \"%28x-3%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"2%28%28x-3%29%5E2%2B5%2F2%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x-3%29%5E2%2B2%285%2F2%29\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x-3%29%5E2%2B5\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "So after completing the square, \"2x%5E2-12x%2B23\" transforms to \"2%28x-3%29%5E2%2B5\". So \"2x%5E2-12x%2B23=2%28x-3%29%5E2%2B5\" for all real values of 'x'.\r
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