SOLUTION: Please solve following quadratic equations using method completing the square: x^2 + x = -1

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Question 15483: Please solve following quadratic equations using method completing the square:
x^2 + x = -1
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by completing the square:
x%5E2+%2B+x+=+-1 Complete the square in the x-terms by adding the square of half the coefficient of the x-term to both sides. This means adding %281%2F2%29%5E2+=+1%2F4 to both sides.
x%5E2+%2B+x+%2B+1%2F4+=+-1+%2B+1%2F4 Factor the left side.
%28x+%2B+1%2F2%29%5E2+=+-3%2F4 Take the square root of both sides.
x+%2B+1%2F2+=+sqrt%28-3%2F4%29 Subtract 1%2F2 from both sides.
x+=+sqrt%28-3%2F4%29+-+1%2F2 Simplify.
x+=+%281%2F2%29sqrt%28-3%29+-+1%2F2
x+=+%28-1+-+sqrt%283%29i%29%2F2 and/or x+=+%28-1+%2B+sqrt%283%29i%29%2F2