document.write( "Question 189904: Solve by completing the square.
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\n" ); document.write( " y^2 - 12y = -11
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Algebra.Com's Answer #142492 by jim_thompson5910(35256)\"\" \"About 
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\"y%5E2+-+12y+=+-11\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y%5E2+-+12y+%2B11=0\" Add 11 to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y%5E2-12y%2B11\" Start with the left side of the equation.\r
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\n" ); document.write( "\n" ); document.write( "Take half of the \"y\" coefficient \"-12\" to get \"-6\". In other words, \"%281%2F2%29%28-12%29=-6\".\r
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\n" ); document.write( "\n" ); document.write( "Now square \"-6\" to get \"36\". In other words, \"%28-6%29%5E2=%28-6%29%28-6%29=36\"\r
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\n" ); document.write( "\n" ); document.write( "\"y%5E2-12y%2Bhighlight%2836-36%29%2B11\" Now add and subtract \"36\". Make sure to place this after the \"y\" term. Notice how \"36-36=0\". So the expression is not changed.\r
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\n" ); document.write( "\n" ); document.write( "\"%28y%5E2-12y%2B36%29-36%2B11\" Group the first three terms.\r
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\n" ); document.write( "\n" ); document.write( "\"%28y-6%29%5E2-36%2B11\" Factor \"y%5E2-12y%2B36\" to get \"%28y-6%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28y-6%29%5E2-25\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So after completing the square, \"y%5E2-12y%2B11\" transforms to \"%28y-6%29%5E2-25\". So \"y%5E2-12y%2B11=%28y-6%29%5E2-25\".\r
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\n" ); document.write( "\n" ); document.write( "So \"y%5E2-12y%2B11=0\" is equivalent to \"%28y-6%29%5E2-25=0\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28y-6%29%5E2-25=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"%28y-6%29%5E2=0%2B25\"Add \"25\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"%28y-6%29%5E2=25\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x-6=%22%22%2B-sqrt%2825%29\" Take the square root of both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y-6=sqrt%2825%29\" or \"y-6=-sqrt%2825%29\" Break up the \"plus/minus\" to form two equations.\r
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\n" ); document.write( "\n" ); document.write( "\"y-6=5\" or \"y-6=-5\" Take the square root of \"25\" to get \"5\".\r
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\n" ); document.write( "\n" ); document.write( "\"y=6%2B5\" or \"y=6-5\" Add \"6\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y=11\" or \"y=1\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"y=11\" or \"y=1\".
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