SOLUTION: On two occasions last month, Sam rented a car on a business trip. Both times it was the same model from the same company, and both times it was in San Francisco. Sam now has to fil

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Question 204855This question is from textbook beginning algebra
: On two occasions last month, Sam rented a car on a business trip. Both times it was the same model from the same company, and both times it was in San Francisco. Sam now has to fill out an expense account form and needs to know how much he was charged per mile and the base rate. On both occasions he only got the total charge and not the details. All Sam knows is that he was charged $210 on for 625 mi on the first occasion and $133.50 for 370 mi on the second trip. Plot these two points on a graph and draw a line that goes through them.
After plotting these two points on a graph and drawing the line that goes through them, answer the following:
What is the equation of the line in the slope intercept form of the equation?
In your own words, explain what question the slope of the line answers for Sam.
What does the y intercept tell Sam and how does it help him?




This question is from textbook beginning algebra

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
On both occasions he only got the total charge and not the details. All Sam knows is that he was charged $210 on for 625 mi on the first occasion and $133.50 for 370 mi on the second trip. Plot these two points on a graph and draw a line that goes through them.
After plotting these two points on a graph and drawing the line that goes through them, answer the following:
What is the equation of the line in the slope intercept form of the equation?
slope = (210-133.5)/(626-370) = 0.2988
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intercept?
210 = 0.2988*625 + b
b = 23.23
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Equation:
Charge = slope*miles + intercept
C(m) = 0.2988m + 23.23
graph%28400%2C300%2C-100%2C700%2C-100%2C250%2C0.2988x%2B23.23%29
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In your own words, explain what question the slope of the line answers for Sam.
For each additional mile the charge goes up 0.2988 dollars or about 30 cents.
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What does the y intercept tell Sam and how does it help him?
The initial charge for renting the car is $23.23
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Cheers,
Stan H.