Answer:
1
Step-by-step explanation:
The function f(x)=x+6*2 can be rewritten as f(x)=x+12
The average rate of change on the function f on [a,b] interval is the ratio of the changes [tex]\frac{\bigtriangleup f}{\bigtriangleup x }[/tex] :
[tex]\bigtriangleup=\frac{f(b)-f(a)}{b-a}[/tex]
We determine our substitute our interval values in the function:
[tex]f(9)=9+12=21\\\\f(4)=4+12=16\\\\\bigtriangleup=\frac{21-16}{9-4}\\\\=1[/tex]
Hence, the average rate of change is 1
