SOLUTION: Solve by completing the square x^2 - x - 1 = 0 Thanks

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Question 203133: Solve by completing the square
x^2 - x - 1 = 0
Thanks
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for x by completing the square:
x%5E2-x-1+=+0 First add 1 to both sides.
x%5E2-x+=+1 Now complete the square in x by adding the square of half the x-coefficient (%28-1%2F2%29%5E2+=+1%2F4 to both sides.
x%5E2-x%2B1%2F4+=+1%2B1%2F4 Factor the left side and simplify the right side.
%28x-1%2F2%29%5E2+=+5%2F4 Take the square root of both sides.
x-1%2F2+=+sqrt%285%29%2F2 (+ or -) in front of the sq.rt. Now add 1%2F2 to both sides.
highlight%28x+=+%281%2F2%29%2B-sqrt%285%29%2F2%29 or highlight_green%28x+=+%281%2B-sqrt%285%29%29%2F2%29