SOLUTION: solve the equation by completing the square x^2+6x+2=0

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Question 134075: solve the equation by completing the square
x^2+6x+2=0
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B6x%2B2=0

Step 1: Move the constant term to the right hand side of the equation:

x%5E2%2B6x=-2

Step 2: Divide the coefficient on the 1st degree term by 2

6%2F2=3

Step 3: Square the result of Step 2:

3%5E2=9

Step 4: Add the result of Step 3 to both sides of the equation:

x%5E2%2B6x%2B9=-2%2B9
x%5E2%2B6x%2B9=7

Step 5: The left side of the equation is now a perfect square, so factor it:

%28x%2B3%29%5E2=7

Step 6: Take the square root of both sides, remembering to consider both the positive and negative roots:

x%2B3=sqrt%287%29 or x%2B3=-sqrt%287%29

Step 7: Isolate x:

x=-3%2Bsqrt%287%29 or x=-3-sqrt%287%29

Step 8: Check your answers