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

So to start, we need to put this information into slope-intercept form. Slope intercept form is [tex]y=mx+b[/tex] where [tex]m[/tex] represents the slope of a line and [tex]b[/tex] represents the y-intercept. In this question [tex]y[/tex] represents the total cost of the rental, [tex]x[/tex] represents the number of miles driven, [tex]m[/tex] represents the price per mile, and [tex]b[/tex] 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 [tex]y=.50x+120[/tex]

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

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

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

Now, we are trying to find [tex]x[/tex] so we need to isolate the variable.

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

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

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

This means that at [tex]200[/tex] miles, both companies will cost the same amount.