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Answer:</h2>

The solution for x in this equation is <em>18</em>.<em> </em>
Answer:
15x + 40 = 115
We set the equation to 115 because the total cost is $115.
We add the "+ 40" because of the $40 to rent the trailer for the day.
The 15x is because it represents the miles per hour (x) times the number of hours.
The number of hours times the charge per mile, plus the $40 to rent it, will equal $115.
Hope this helps!!
The y intercept is seven so you would start by placing a point on (0,7). Then you count Down four points because the slope is a negative number and then count nine points to the right. You would have to keep counting down four points and the right nine points until your line was long enough.