Question 204855
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(400,300,-100,700,-100,250,0.2988x+23.23)}}}
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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.