Question

Write an equation for the vertical line E(-5,-9)

Answer 1

any vertical line is of the form x = h where h is any real number

in this case, h must be -5 because that's the x coordinate of the point (-5, -9)

so the equation of the vertical line is x = -5

Answer 2

another way to think of it:

the line x = -5 has points on it where each point has an x coordinate of -5