That is the graph ^
The Graph is a line y=m*x+b slope m and y-intercept-b are constant values... Solutions are the ordered pairs (X,Y) that lie on the line
Just look at the graph in this case and see, for A) (X,Y) = (-2,-3) When X=-2, does Y =-3 ? Is that point on the line?
at least - not in this case and since he supplied a wrong answer with no help or explanation - I suggest you can't really trust him at all