Answer:
- 2
Explanation:
Since the function is linear then the average rate of change is the measure of the slope of the line.
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
y = - 2x + 70 ← is in slope- intercept form
with slope m = - 2
Thus rate of change is - 2