Viewing the two equations (by graphing them), we can see that the y axis is the vertical one and the x axis is the horizontal one. If something were to be reflected over the y axis, it would be flipped around x=0 and the x value of every point would be multiplied by -1. If it was reflected over the x axis (y=0), every y value would be multiplied by -1. Taking two points that have the same absolute values, e.g. (-1, 0) and (1, 0) (by absolute values I mean that (|-1|, |0|)=(|1|, |0|)=(1, 0)) we can see that -1*-1=1 and 1*-1=-1. Since they are the x values, it is reflected across the y axis - you are correct!