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
The answer to your question is x= -12 hope this helps ! Makes sure you put the negative !
Answer:
Isolate the variable by dividing each side by factors that don't contain the variable
Exact Form:
x = - 25/8 
Decimal Form:
x = -3.125
Mixed Number Form:
x = - 3/1/8 
Step-by-step explanation:
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