Answer:
The average rate of change is 8.
Step-by-step explanation:
The formula to calculate the average rate of change of a function F(x) is:

In this case, F(x) = 
a=2 and b=4
You have to evaluate x=2 (which is a in the formula) and x=4 (which is b in the formula) in the function.
In order to obtain F(b) and F(a) you have to replace x=4 and x=2 in the given function:
F(b) = 
F(a) = 

The answer is 8.
2x+10=3x-15
25=x when simplified
Answer:

Step-by-step explanation:
See attached file for complete work.