SOLUTION: I need to solve using Completing the square x squared=-4x-2

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Question 283671: I need to solve using Completing the square
x squared=-4x-2

Found 2 solutions by richwmiller, oberobic:
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
x^2=-4x-2
x^2+4x=-2
take (4/2)^2=2^2=4
add 4 to both sides
x^2+4x+4=2
(x+2)^2=2
x=-2+sqrt(2)
x=-2-sqrt(2)

Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2+=+-4x+-2
.
Add 4x to both sides
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x%5E2+%2B4x+=+-2
.
This is conceptually ax^2 + bx = c
.
To complete the square, take 1/2*b, square it, and add it as a new 'c'.
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x%5E2+%2B4x++=+-2
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%281%2F2%29%2A4+=+2
2%5E2+=+4
.
x%5E2+%2B4x+%2B4+=+-2
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%28x%2B2%29%28x%2B2%29+=+-2
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%28x%2B2%29%5E2+=+-2
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hmmmm....that means we have an imaginary number in here, since we have a squared term on the left and a negative number on the right.
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x%2B2+=+sqrt%28-2%29+=+i%2Asqrt%282%29
.