document.write( "Question 191078: Please help me solve this equation
\n" ); document.write( "5-5 Completing the Square\r
\n" ); document.write( "\n" ); document.write( " Solving a quadratic equation if the coefficient of x^2 is NOT 1\r
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\n" ); document.write( "\n" ); document.write( " 4x^2+24x-8=0
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Algebra.Com's Answer #143444 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
First, let's complete the square for the left side of the equation \"4x%5E2%2B24x-8=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"4x%5E2%2B24x-8\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"4%28x%5E2%2B6x-2%29\" Factor out the \"x%5E2\" coefficient \"4\". 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 \"6\" to get \"3\". In other words, \"%281%2F2%29%286%29=3\".\r
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\n" ); document.write( "\n" ); document.write( "Now square \"3\" to get \"9\". In other words, \"%283%29%5E2=%283%29%283%29=9\"\r
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\n" ); document.write( "\n" ); document.write( "\"4%28x%5E2%2B6x%2Bhighlight%289-9%29-2%29\" Now add and subtract \"9\" inside the parenthesis. Make sure to place this after the \"x\" term. Notice how \"9-9=0\". So the expression is not changed.\r
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\n" ); document.write( "\n" ); document.write( "\"4%28%28x%5E2%2B6x%2B9%29-9-2%29\" Group the first three terms.\r
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\n" ); document.write( "\n" ); document.write( "\"4%28%28x%2B3%29%5E2-9-2%29\" Factor \"x%5E2%2B6x%2B9\" to get \"%28x%2B3%29%5E2\".\r
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\n" ); document.write( "\n" ); document.write( "\"4%28%28x%2B3%29%5E2-11%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"4%28x%2B3%29%5E2%2B4%28-11%29\" Distribute.\r
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\n" ); document.write( "\n" ); document.write( "\"4%28x%2B3%29%5E2-44\" Multiply.\r
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\n" ); document.write( "\n" ); document.write( "So after completing the square, \"4x%5E2%2B24x-8\" transforms to \"4%28x%2B3%29%5E2-44\". So \"4x%5E2%2B24x-8=4%28x%2B3%29%5E2-44\".\r
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\n" ); document.write( "\n" ); document.write( "So \"4x%5E2%2B24x-8=0\" is equivalent to \"4%28x%2B3%29%5E2-44=0\".\r
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\n" ); document.write( "\n" ); document.write( "Now let's solve \"4%28x%2B3%29%5E2-44=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"4%28x%2B3%29%5E2-44=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"4%28x%2B3%29%5E2=44\" Add 44 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29%5E2=%2844%29%2F%284%29\" Divide both sides by \"4\".\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B3%29%5E2=11\" Reduce.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B3=%22%22%2B-sqrt%2811%29\" Take the square root of both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B3=sqrt%2811%29\" or \"x%2B3=-sqrt%2811%29\" Break up the \"plus/minus\" to form two equations.\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3%2Bsqrt%2811%29\" or \"x=-3-sqrt%2811%29\" Subtract \"3\" from 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=-3%2Bsqrt%2811%29\" or \"x=-3-sqrt%2811%29\".\r
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