Not sure what that is. Graphing is easy. You just gotta think about it the right way. I tried to explain it the way I comprehend graphs.
For example, miles per hour. 60mph means 60 miles for every 1 hour. That is 60 for every 1. The slope of 60mph would be 60. So in X=1 hours, Y=60 miles. X=2 hours, Y=120 miles.

Now for b.
y = (-8/19)x + b
b is calculated by using X = 0, because when X is zero, m doesn't matter, because mx = m * 0 = 0, leaving you with y = m * 0 + b = 0 + b = b.
y = b when x = 0
So, to find what b is, we find what y is when x is zero, given what we already know.

I'm going to use Point A, since it's easier to count forwards than backwards.
Point A: (-16, 14)
y = (-8/19)x + b
We are currently (at Point A) 16 units away from X = 0. And we know that for every unit, we're going to decrease by 8/19. So, 16 * -8/19 = -128/19. So, 16 units away from Point A, the Y value should have decreased by 128/19 (that is, 16 of -8/19).
At Point A, the Y value is 14. 128/19 less than that is 14 - 128/19 = 266/19 - 128/19 (converted 14 to 266/19 so that we can subtract fractions) = (266 - 12/19 = 138/19
So the Y value 16 units ahead of Point A is 138/19. That is, the Y value 16 units ahead of X = -16, or the Y value at X = 0, is 138/19.
And since the Y value at X = 0 is b, because:
y = mx + b = m * 0 + b = 0 + b = b
Then y = 138/19 = b. So, b = 138/19
y = mx + b = (-8/19)x + 138/19

This would be so much easier to teach if we had whole numbers.