Given:
Fixed charges = $40
Variable charges = $1.70 for each mile.
To find:
The equation that represents the total cost y for x miles towed.
Find the y-intercept and interpret its meaning in the context of the situation.
Solution:
Let y be the total cost for x miles.
Fixed charges = $40
Variable charges for 1 mile = $1.70
Variable charges for x mile = $1.70x
Now,
Total changes = Fixed charges + Variable changes

Therefore, the required equation is
.
Putting x=0 in the above equation, we get



Therefore, the y-intercept is 40. It means the charges to hook a car is $40 if it is towed 0 miles.