What are some real life situations using system of equations?

Bob's car rental company makes you pay 10 dollars per day you rent the car and a 30 dollar insurance fee

joe's car rental company makes you pay 30 dollars per day you rent the car and a 10 dollar insurance fee

how many days do you need to rent a car for the cost for renting both are the same

bob=10x+30

joe=30x+10

set each to each other

10x+30=30x+10

subtract 10x

30=20x+10

subtract 10

20=20x

divide both sides by 20

1=x

you need to rent 1 day for them to be equal