document.write( "Question 189934: Hello.
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Algebra.Com's Answer #142509 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"-2+=+2x%5E2+-+5x+\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"0+=+2x%5E2+-+5x+%2B2+\" Add 2 to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2+-+5x+%2B2+=+0\" Rearrange the equation\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%5E2-%285%2F2%29x%2B1%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 \"-5%2F2\" to get \"-5%2F4\". In other words, \"%281%2F2%29%28-5%2F2%29=-5%2F4\".\r
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\n" ); document.write( "\n" ); document.write( "Now square \"-5%2F4\" to get \"25%2F16\". In other words, \"%28-5%2F4%29%5E2=%28-5%2F4%29%28-5%2F4%29=25%2F16\"\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%5E2-%285%2F2%29x%2Bhighlight%2825%2F16-25%2F16%29%2B1%29\" Now add and subtract \"25%2F16\" inside the parenthesis. Make sure to place this after the \"x\" term. Notice how \"25%2F16-25%2F16=0\". So the expression is not changed.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28%28x%5E2-%285%2F2%29x%2B25%2F16%29-25%2F16%2B1%29\" Group the first three terms.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28%28x-5%2F4%29%5E2-25%2F16%2B1%29\" Factor \"x%5E2-%285%2F2%29x%2B25%2F16\" to get \"%28x-5%2F4%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"2%28%28x-5%2F4%29%5E2-9%2F16%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x-5%2F4%29%5E2%2B2%28-9%2F16%29\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x-5%2F4%29%5E2-9%2F8\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "So after completing the square, \"2x%5E2-5x%2B2\" transforms to \"2%28x-5%2F4%29%5E2-9%2F8\". So \"2x%5E2-5x%2B2=2%28x-5%2F4%29%5E2-9%2F8\".\r
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\n" ); document.write( "\n" ); document.write( "So \"2x%5E2-5x%2B2=0\" is equivalent to \"2%28x-5%2F4%29%5E2-9%2F8=0\".\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x-5%2F4%29%5E2-9%2F8=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x-5%2F4%29%5E2=0%2B9%2F8\"Add \"9%2F8\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x-5%2F4%29%5E2=9%2F8\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-5%2F4%29%5E2=%289%2F8%29%2F%282%29\" Divide both sides by \"2\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-5%2F4%29%5E2=9%2F16\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"x-5%2F4=%22%22%2B-sqrt%289%2F16%29\" Take the square root of both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x-5%2F4=sqrt%289%2F16%29\" or \"x-5%2F4=-sqrt%289%2F16%29\" Break up the \"plus/minus\" to form two equations.\r
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\n" ); document.write( "\n" ); document.write( "\"x-5%2F4=3%2F4\" or \"x-5%2F4=-3%2F4\" Take the square root of \"9%2F16\" to get \"3%2F4\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=5%2F4%2B3%2F4\" or \"x=5%2F4-3%2F4\" Add \"5%2F4\" to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x=2\" or \"x=1%2F2\" 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=2\" or \"x=1%2F2\".
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