THE PROPER PICTURE for the question is posted above in this topic.Note, that the line
x = -4 is parallel
to the y-axis and crosses the
x-axis at the point (-4, 0).
The line
y =
x and the line
y = -4 are different lines. These two lines cross at the point (-4, -4), which happens to be the crossing point of the lines
y =
x and
x = -4 as well.
The following picture demonstrates that the lines
y =
x and
y = -4 are different:
THE PROPER PICTURE for the question is posted above in this topic.