document.write( "Question 147242: Solve by completing the square:
\n" ); document.write( "x^2 + 6x + 1 = 0
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Algebra.Com's Answer #107620 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\"x%5E2%2B6x%2B1\" Start with the given expression\r
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\n" ); document.write( "\n" ); document.write( "Take half of the x coefficient \"6\" to get \"3\" (ie \"%281%2F2%29%286%29=3\").\r
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\n" ); document.write( "\n" ); document.write( "Now square \"3\" to get \"9\" (ie \"%283%29%5E2=%283%29%283%29=9\")\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B6x%2B9-9%2B1\" Now add and subtract this value inside the parenthesis. Notice how \"9-9=0\". Since we're adding 0, we're not changing the equation.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29%5E2-9%2B1\" Now factor \"x%5E2%2B6x%2B9\" to get \"%28x%2B3%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29%5E2-8\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "So after completing the square, \"x%5E2%2B6x%2B1\" becomes \"%28x%2B3%29%5E2-8\".\r
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\n" ); document.write( "\n" ); document.write( "In other words, \"x%5E2%2B6x%2B1=%28x%2B3%29%5E2-8\"\r
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\n" ); document.write( "\n" ); document.write( "So \"x%5E2%2B6x%2B1=0\" is equivalent to \"%28x%2B3%29%5E2-8=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29%5E2-8=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29%5E2=8\" Add 8 to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B3=0%2B-sqrt%288%29\" Take the square root of both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3%2B-sqrt%288%29\" Subtract 3 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3%2Bsqrt%288%29\" or \"x=-3-sqrt%288%29\" Break up the expression\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3%2B2%2Asqrt%282%29\" or \"x=-3-2%2Asqrt%282%29\" Simplify the square root.\r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x=-3%2B2%2Asqrt%282%29\" or \"x=-3-2%2Asqrt%282%29\"\r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=-0.172\" or \"x=-5.828\"
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