Hi Maybe!
Essentially it's a vertical line crossing directly over the number -2 in the x-axis. Also, the question asks for an equation (=). Therefore x = -2.
Here's a tip and mental note you should keep: As I told another fellow student, stuff like y = h (or even y </>/≤/≥ h) all result in horizontal lines with those lines crossing directly over h. x = v (or even x </>/≤/≥ v) all result in vertical lines crossing directly over v.