When there is a negative in squre root, it means imaginary number come in. 'i' is usually the varible used to identify imaginary numbers.
First remove the negative from the square root and find the square root of 4, which is 2. Then add i to 2. 2i
Now solve for the positive then negative.
-2 + 2i
----------- = -1 + 1i
2
-2 - 2i
----------- = -1 - 1i
2
Both -1 + 1i and -1 - 1i are the answers.
