Answer :
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