Respuesta :

Here, first we need to calculate the slope, 
m = y2-y1 / x2-x1
m = 4-4 / 5-2
m = 0

Now, y - y1 = m( x - x1)
y - 4 = 0 (x - 2)
y = 4

In short, Your whole equation would be: y = 4

Hope this helps!