For this case we have the following info given
x y
-20 96
-12 60
-6 33
-2 15
And we want to estimate the rate of change
Solution
For this case we can use the following formula:
m= (y2-y1)/(x2-x1)
And we can use x1= -20 y1= 96
x2= -12, y2= 60
And if we replace into the formula we got:
m= (60-96)/( -12+20)
m= -36/8
And if we simplify we got:
m=-9/2