You can do this in multiple ways. Firstly, you can make a table. (this is if you do not have an equation) you do :
x | y
------
0 | 7
1 | 29 for example. You check the ammount it goes up by so its delta y over delta x. DeltaY ^~^
--------
DeltaX
So from 0 to 1 is +1 The y-intercept or the 0 term is 7 in this case. So your equation would be, Y= 22X + 7 since 7 is postive.
And 22x is the slope.
another way is with an equation, it is simply the number with the x attached. if it is a number 22x itss 22 over 1 x :3
Thats all i got to help you :D hope this helps