document.write( "Question 195673: Solve the equation by completing the square. Round to the nearest hundredth if necessary.
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Algebra.Com's Answer #146738 by jim_thompson5910(35256)\"\" \"About 
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\"3x%5E2-6x-24\" Start with the left side of the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x%5E2-2x-8%29\" Factor out the \"x%5E2\" coefficient \"3\". 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 \"-2\" to get \"-1\". In other words, \"%281%2F2%29%28-2%29=-1\".\r
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\n" ); document.write( "\n" ); document.write( "Now square \"-1\" to get \"1\". In other words, \"%28-1%29%5E2=%28-1%29%28-1%29=1\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x%5E2-2x%2Bhighlight%281-1%29-8%29\" Now add and subtract \"1\" inside the parenthesis. Make sure to place this after the \"x\" term. Notice how \"1-1=0\". So the expression is not changed.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28%28x%5E2-2x%2B1%29-1-8%29\" Group the first three terms.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28%28x-1%29%5E2-1-8%29\" Factor \"x%5E2-2x%2B1\" to get \"%28x-1%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"3%28%28x-1%29%5E2-9%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x-1%29%5E2%2B3%28-9%29\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x-1%29%5E2-27\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "So after completing the square, \"3x%5E2-6x-24\" transforms to \"3%28x-1%29%5E2-27\". So \"3x%5E2-6x-24=3%28x-1%29%5E2-27\".\r
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\n" ); document.write( "\n" ); document.write( "So \"3x%5E2-6x-24=0\" is equivalent to \"3%28x-1%29%5E2-27=0\".\r
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\n" ); document.write( "\n" ); document.write( "Now let's solve \"3%28x-1%29%5E2-27=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x-1%29%5E2-27=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x-1%29%5E2=0%2B27\"Add \"27\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x-1%29%5E2=27\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-1%29%5E2=%2827%29%2F%283%29\" Divide both sides by \"3\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-1%29%5E2=9\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"x-1=0%2B-sqrt%289%29\" Take the square root of both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x-1=sqrt%289%29\" or \"x-1=-sqrt%289%29\" Break up the \"plus/minus\" to form two equations.\r
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\n" ); document.write( "\n" ); document.write( "\"x-1=3\" or \"x-1=-3\" Take the square root of \"9\" to get \"3\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=1%2B3\" or \"x=1-3\" Add \"1\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x=4\" or \"x=-2\" 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 \"x=4\" or \"x=-2\".
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