Answer:
y = x + 9
y = x + 8
Explanation:
The line in each graph goes through either 9, -9, 8, or -8 so you know if it is negative or positive and if it is negative I'm pretty sure you do y = x - 9, but if it's a postive you do y = x = 9. (sorry if I'm wrong I haven't done this math in a while)