So the dots are going at a slope of 1 up and 1 right each time, so your slope would be 1, or simply x if you times it. To line it up with the slope, you have to move up 5 on your y-axis, known as your b. Then from there, you go up 1 over 1 which will line up with all the dots.
We can remove 6 cubes on each side and still make them balance. And we got 4 bags = 16 cubes, them we divide by 4 on each side, we can get 4 cube is in each bag.