It should be f since you can subtract from both sides and divide by negative 1
Is there more context to the question?
100-30=70-50=20
there's your equation
Y-Intercept =(−8)
Go to the graph and plot the point the point (0,−8) on the y-axis.
Then rise 4 and run 1. Plot the point (1,−4)
Then again "rise 4" and then "run" 1. Plot the point (2,0)