——–

x2-x1

So now just plug in the #s using only two points…so bus 1 and bus 2 would look like this m=100-80 / 5-8 so m=20/-3 so the slope is -20 over 3

On a graph you would go down 20 and over to the right 3 to plot all your pts

bus number- x

gas used- y

the equation looks like this

y1-y2

———

x1-x2

that means you take one y (easiest would be the largest y) minus a different y (the smallest y)

divide by the largest x minus the smalles x

and remember you have to subtract both sides before you can divide

the finale equation is y = mx + b

m is your slope

so it would be y(any y you chose) = (your new slope) times (any x you chose) + b