Answer:
2
Step-by-step explanation:
Use the formula: change of y over change of x.
When you do that, your systems should look like this:
x1 = 2
y1 = 4
x2 = 6
y2 = 12
After that you plug these number into the corresponding variable.
(12 - 4) / (6 - 2) = 8/4 which equals 2.