Sonya is renting a car. She pays a fee of $50 for the rental plus $20 each day she had the car. Suppose she pays a total for $130. For how many days did she rent the car?

Answer: she rented the car for 4 days.

Step-by-step explanation:

Let x represent the number of days for which Sonya rented the car.

She pays a fee of $50 for the rental plus $20 each day she had the car. This means that if she rents the car of x days, the total amount that she would pay is

20x + 50

Suppose she pays a total for $130, it means that the number of days for which she rented the car would be

20x + 50 = 130

Subtracting 50 from the left hand side and the right hand side of the equation, it becomes

20x + 50 - 50 = 130 - 50

20x = 80

x = 80/20 = 4