quadratic equation / completing the square

[mega6]

Problem: x^2 - 2x = -2
I complete the square to get: x^2 - 2x +1 = -2+1
Then: (x-1)^2 = -1
I want to take the square root of each side, but I don't remember what to do with a square root of a negative number

 

[mmm4444bot]

sqrt(-1) is defined by the symbol i.

i = sqrt(-1)

3i = sqrt(-9) because sqrt(-9) = sqrt(-1)*sqrt(9) by property.

Ring any bells?