To find the equation of the line we will need to find slope and the y-intercept.
Given: (-3,9), (-3,-5)
What we know:
slope=m=(y2-y1)/(x2-x1)
m=(-5-9)/9-3-(-3))=-14/0
m=undefined
When slope=m is undefined we have an a line x=-3. That means that for every y the x value is always -3. This line x=-3 is a vertical line on the graph at -3.