The linear function that models the total cost for x deliveries is:

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A linear function has the following format:

In which
- m is the slope, that is, the rate of change.
- b is the y-intercept, that is, the value of y when x = 0.
In this problem:
- Fixed cost of $9 per month,
. - Cost of $2 for each delivery, thus
.
The function for the <u>total cost for x deliveries is:</u>

A similar problem is given at brainly.com/question/16270359
7.16 dpollars for one candy bar
Here's a way to do it.
Let 4e +2 = 5n +1 . . . . . . for some integer n
Then e = (5n -1)/4 = n + (n -1)/4
We want (n-1)/4 to be an integer, so let it be integer m.
... m = (n -1)/4
... 4m = n -1
... 4m +1 = n
Substituting this into our expression for e gives
... e = (5(4m+1) -1)/4 = (20m +4)/4 = 5m +1
e = 5m+1 for any integer m
The additive inverse of a number is just the opposite of the given number. For example; 2 and the additive inverse is -2.
If we apply this to the number we are given, we get 19.57
Best of Luck!