document.write( "Question 147430: Solve by completing the square:
\n" ); document.write( "x^2 + 6x + 1 = 0
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Algebra.Com's Answer #107810 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
This site describes it quite well:
\n" ); document.write( "http://www.purplemath.com/modules/solvquad3.htm
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\n" ); document.write( "x^2 + 6x + 1 = 0
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\n" ); document.write( "First, isolate the x's -- so, subtract 1 from both sides:
\n" ); document.write( "x^2 + 6x = -1
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\n" ); document.write( "Next, look at the coefficient associated with the x term (6). Divide this by 2 and square it to get 9.
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\n" ); document.write( "So, we ADD 9 to both sides:
\n" ); document.write( "x^2 + 6x + 9 = -1 + 9
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\n" ); document.write( "Now, we factor the left side and combine the right to get:
\n" ); document.write( "(x+3)(x+3) = 8
\n" ); document.write( "(x+3)^2 = 8
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\n" ); document.write( "To solve:
\n" ); document.write( "(x+3)^2 = 8
\n" ); document.write( "Take the square root of both sides:
\n" ); document.write( "x + 3 = (+-)sqrt(8)
\n" ); document.write( "x = (+-)sqrt(8) - 3
\n" ); document.write( "x = (+-)2sqrt(2) - 3
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\n" ); document.write( "Note: the (+-) means \"plus or minus\"
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