Question

x =4 is because x is always the horizontal line on the graph and 4 would be the vertical line?

Answer 1

not, the value of x is always constant no matter what y is, and the value of x is constant on this vertical line. so you have x=-4 as vertical line.

Answer 2

the graph shows x=4

Answer 3

Thank you

Answer 4

If you are asked to describe or draw the graph of x = 4 and you are uncertain, you can always make up two points with ordered pairs of the form (4, anything). Example: (4, 2) and (4, -3). Quickly sketch the graph on paper or in your head. You'll see that the points stack up vertically. So, x = 4 is a vertical line. x is stuck on 4 and y has no restrictions.

You can do a similar process for y = 4 if you are confused whether it is a vertical or horizontal line. Your "test points" would be of the form (anything, 4).

The confusion here always reminds me of lattitude and longitude. Lattitude circles run "horizontally" but measure distance north and south.