SOLUTION: x2+4x+2=0 c.s

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Question 696399: x2+4x+2=0 c.s
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
No one else knew what you wanted or meant, but I read minds.

x%5E2%2B4x%2B2=0

Completing the Square:
The square that starts with x%5E2%2B4x is
x%5E2%2B4x%2B4=%28x%2B2%29%5E2
Adding 2 to each side of x%5E2%2B4x%2B2=0 we get
x%5E2%2B4x%2B4=2 , which we can re-write as
%28x%2B2%29%5E2=2, which means that
either x%2B2=sqrt%282%29,
or x%2B2=-sqrt%282%29.
x%2B2=sqrt%282%29 means x=-2%2Bsqrt%282%29
x%2B2=-sqrt%282%29 means x=-2-sqrt%282%29
Both values of x are solutions of x%5E2%2B4x%2B2=0.
We can write both solutions as
highlight%28x=-2+%2B-+sqrt%282%29%29