Question

x^2=-9

Answer 1

\[x = \sqrt{-9}\]
Imaginary solutions.
\[x = \pm 3j\]

Answer 2

is it always, sometimes, or never?

Answer 3

Have you covered imaginary solutions?
If not, then never.

Answer 4

what property did you use to solve it?

Answer 5

Erm, not sure about that.