document.write( "Question 143032: Solve by completing the square\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B8+x=-15\"
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Algebra.Com's Answer #104074 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%2B8+x=-15\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "Take half of the x coefficient \"8\" to get \"4\" (ie \"%281%2F2%29%288%29=4\").\r
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\n" ); document.write( "\n" ); document.write( "Now square \"4\" to get \"16\" (ie \"%284%29%5E2=%284%29%284%29=16\")\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B8+x%2B16=-15%2B16\" Add this value to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B8+x%2B16=1\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B4%29%5E2=1\" Now factor \"x%5E2%2B8x%2B16\" to get \"%28x%2B4%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B4=0%2B-sqrt%281%29\" Take the square root of both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B4=1\" or \"x%2B4=-1\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3\" or \"x=-5\" Simplify Subtract \"4\" from both sides in each case\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-3\" or \"x=-5\" \r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph we can see that the roots are \"x=-3\" and \"x=-5\". So this verifies our answer.\r
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\n" ); document.write( "\n" ); document.write( "\"graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C+x%5E2%2B8x%2B15%29\"
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