Question 31544
First of all you need to find the slope. Since the line is perpendicular to the x-axis there is no slope. Using the formula y-y1=m(x-x1) we can plug in the numbers.

1st method:

y-y1=m(x-x1)
y-4=m(x--2)
y-4=m(x+2)
y-4=0(x+2)
y-4=0
y=4
 
Or 2nd method:

standard form: y=mx+b
               y=0(-2)+4
               y=4

Hope i helped :)