The graph below plots a function f(x): graph of line segment going through ordered pairs 0, 50 and 2,100 and extend beyond 2,100 if x represents time, the average rate of change of the function f(x) in the first two seconds is

By definition we have that the average rate of change of the function is given by:
 
 Substituting values we have:
 
 Rewriting we have:
 
 
 
 If x represents time, the average rate of change of the function f(x) in the first two seconds is 25.