The equation of a line is defined by: y=mx+b
Step 1: Find the slope (rise over run) so, the rise is 15.7 and the run is 6. 15.7/6=2.62
y=2.62x+b
Step 2: Find the b value (y intercept) - this is where the line goes through the y axis. In this case, it's 15.7
Step 3: add the slope and the b value together - y=2.62x+15.7
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
Answer: 429.88
Step-by-step explanation:
The first 40 hours is at 9.50
40 *9.50 =380
The remaining hours is at 9.50 * 1.5 or 14.25
43.5 -40 = 3.5
3.5 * 14.25
49.875 = 49.88 ( rounding to the nearest cent)
Add together
380+49.88 =429.88