SOLUTION: x^2+2X=2 how do I complete the square?

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Question 419231: x^2+2X=2 how do I complete the square?
Found 2 solutions by ewatrrr, josmiceli:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!

Hi
completing the square
x^2+2x = 2
recommend thinking what would 'come in handy' to get (x+1)^2 on left side...
and adding that number 1 to both sides of the equation.
x%5E2+%2B+2x+%2B+highlight%281%29+=+2+%2B+highlight%281%29+
(x+1)^2 = 3

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E2+%2B+2x+=+2+
Take 1/2 of the coefficient of x, square it,
and add it to both sides
x%5E2+%2B+2x+%2B+%282%2F2%29%5E2+=+2+%2B+%282%2F2%29%5E2+
x%5E2+%2B+2x+%2B+1+=+2+%2B+1+
The left side is now a perfect square
+%28x+%2B+1%29%5E2++=+3+
Now take the square root of both sides
+x+%2B+1+=+sqrt%283%29+
x+=+-1+%2B+sqrt%283%29+ answer
and
+x+%2B+1+=+-+sqrt%283%29+
x+=+-1+-+sqrt%283%29+ answer
------------------
These 2 answers are the roots. You can check
your work this way:
+x+=+r1
x+=+r2
so,
x+-+r1+=+0
x+-+r2+=+0
so,
x+-+%28-1+%2B+sqrt%283%29%29++=+0
x+-+%28-1+-+sqrt%283%29%29++=+0
so,
+%28x+%2B+1+-+sqrt%283%29%29+%2A+%28x+%2B+1+%2B+sqrt%283%29%29+=+0
Multiplying this out,

+x%5E2+%2B+2x+-+2+=+0+
+x%5E2+%2B+2x+=+2+
OK