document.write( "Question 75813: solve for x by completing the square: x^2+6x=2 \n" ); document.write( "
Algebra.Com's Answer #54443 by bucky(2189)\"\" \"About 
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\"x%5E2%2B6x=2\"
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\n" ); document.write( "The process goes as follows:
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\n" ); document.write( "First look at the coefficient or multiplier of the x term. Take half of that coefficient,
\n" ); document.write( "square the result, and add that number to both sides of the equation.
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\n" ); document.write( "For this problem, the coefficient of the x term is +6. Take half of that and you have +3.
\n" ); document.write( "Square the +3 and you get +9. Add +9 to both sides of the equation to get:
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\n" ); document.write( "\"x%5E2+%2B+6x+%2B+9+=+2+%2B+9\"
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\n" ); document.write( "You have now made the left side of the equation a perfect square. The term that is squared
\n" ); document.write( "is \"%28x+%2B+3%29\" where the +3 comes from half the coefficient of the x term. So the equation
\n" ); document.write( "can be written as:
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\n" ); document.write( "\"%28x%2B3%29%5E2+=+11\"
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\n" ); document.write( "Note that the 11 comes from adding the 2 and 9 on the right side.
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\n" ); document.write( "Now take the square root of both sides and you get:
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\n" ); document.write( "\"x+%2B+3+=+%2Bsqrt%2811%29\" and \"x%2B3+=+-sqrt%2811%29\"
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\n" ); document.write( "Finally, subtract 3 from both sides to get rid of the +3 that is on the left side. When
\n" ); document.write( "you do you get:
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\n" ); document.write( "\"x+=+-3%2Bsqrt%2811%29\" and \"x+=+-3-sqrt%2811%29\"
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\n" ); document.write( "and those are the two values of x that satisfy the equation of the original problem.
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\n" ); document.write( "Hope this helps you to see and understand the process that you use to solve quadratic
\n" ); document.write( "equations by completing the square. The process remains the same, only the numbers
\n" ); document.write( "change for different quadratic equations.
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