document.write( "Question 243530: Solve 7x^2+28x=49 by completing the square. I know you use the formula (b/2)^2 right? \n" ); document.write( "
Algebra.Com's Answer #178397 by jim_thompson5910(35256)\"\" \"About 
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\"7x%5E2%2B28x=49\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"7%28x%5E2%2B4x%29=49\" Factor out the GCF 7 from the left side.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B4x=49%2F7\" Divide both sides by 7.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B4x=7\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B4x%2Bhighlight%284%29=7%2Bhighlight%284%29\" Take half of the 'x' coefficient and square it to get 4. Add this number to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B2%29%5E2=11\" Factor the left side and combine like terms on the right.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B2=%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=-2%2B-sqrt%2811%29\" Subtract 2 from both sides to isolate 'x'.\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=-2%2Bsqrt%2811%29\" or \"x=-2-sqrt%2811%29\"
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