document.write( "Question 189933: Hello.\r
\n" ); document.write( "\n" ); document.write( "Use completing the square to solve each equation:\r
\n" ); document.write( "\n" ); document.write( "x^2 - 4x + 30 = 0\r
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Algebra.Com's Answer #142506 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-4x%2B30\" Start with the left side of the equation.\r
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\n" ); document.write( "\n" ); document.write( "Take half of the \"x\" coefficient \"-4\" to get \"-2\". In other words, \"%281%2F2%29%28-4%29=-2\".\r
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\n" ); document.write( "\n" ); document.write( "Now square \"-2\" to get \"4\". In other words, \"%28-2%29%5E2=%28-2%29%28-2%29=4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-4x%2Bhighlight%284-4%29%2B30\" Now add and subtract \"4\". Make sure to place this after the \"x\" term. Notice how \"4-4=0\". So the expression is not changed.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2-4x%2B4%29-4%2B30\" Group the first three terms.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-2%29%5E2-4%2B30\" Factor \"x%5E2-4x%2B4\" to get \"%28x-2%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-2%29%5E2%2B26\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "So after completing the square, \"x%5E2-4x%2B30\" transforms to \"%28x-2%29%5E2%2B26\". So \"x%5E2-4x%2B30=%28x-2%29%5E2%2B26\".\r
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\n" ); document.write( "\n" ); document.write( "So \"x%5E2-4x%2B30=0\" is equivalent to \"%28x-2%29%5E2%2B26=0\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-2%29%5E2%2B26=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-2%29%5E2=0-26\"Subtract \"26\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-2%29%5E2=-26\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x-2=0%2B-sqrt%28-26%29\" Take the square root of both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x-2=sqrt%28-26%29\" or \"x-2=-sqrt%28-26%29\" Break up the \"plus/minus\" to form two equations.\r
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\n" ); document.write( "\n" ); document.write( "\"x-2=i%2Asqrt%2826%29\" or \"x-2=-i%2Asqrt%2826%29\" Simplify the square root. Note: \"i=sqrt%28-1%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=2%2Bi%2Asqrt%2826%29\" or \"x=2-i%2Asqrt%2826%29\" Add \"2\" to both sides.\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%2Bi%2Asqrt%2826%29\" or \"x=2-i%2Asqrt%2826%29\".\r
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