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A truck can be rented from company A for $120 a day plus $0.50 per mile. Company b chargers $80 a day plus $0.70 per mile to rent the same truck. Part A write a equation. To find the number of miles in a day at which the rental costs for company A and company B are the same Part b solve the equation

User Harathi
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1 Answer

1 vote

Answer:

Part A:
.50x+120 = .70x+80

Part B:
200 miles

Explanation:

So to start, we need to put this information into slope-intercept form. Slope intercept form is
y=mx+b where
m represents the slope of a line and
b represents the y-intercept. In this question
y represents the total cost of the rental,
x represents the number of miles driven,
m represents the price per mile, and
b represents the base price of the rental. Now that we know the variables, we need to plug in the information we have.

Since we know that company A charges $125 a day and $0.50 per mile we would have
y=.50x+120

Since we know that company B charges $80 a day and $0.70 per mile we would have
y=.70x+80

Now that we have two equations we can move onto the next step. We're looking to know the number of miles (
x) that would make the total cost (
y) equal. To do this we can make the equations equal each other since we know that
y will be the same.

Written out, the equation will look like this:
.50x+120 = .70x+80

Now, we are trying to find
x so we need to isolate the variable.

To start we need to put
x on the same side so we'll subtract
.70x from both sides to get
-.20x+120=80

Next, we'll subtract
120 from both sides of the equation to get
-.20x=-40

Finally, we'll divide both sides by
-.20 to get
x=200

This means that at
200 miles, both companies will cost the same amount.

User Papezjustin
by
5.2k points