Help! What is the average rate of change of f(x)=x^2+3x+6 over the interval -3 less-than-or-equal-to x less-than-or-equal-to 3?

The average rate of change of the function over the interval is 5.

Step-by-step explanation:

Average rate of change of a function:

The average rate of change of a function f(x) over an interval [a,b] is given by:

Interval -3 less-than-or-equal-to x less-than-or-equal-to 3

This means that

So

Average rate of change

The average rate of change of the function over the interval is 5.

If this is asking which company is cheaper then that would be talk time because 1/2 an hour costs $1.25 so if you double that it’s 2.50 then double that and you get 5.00. Add 2.50 one more time and you get 7.50 then add 1.25 and you get 8.75. In the end talk time will be cheaper by $1.25