Jack is renting a boat to go fishing with his friends. One rental company charges a fee of $20 plus $13.50 an hour. A second rental company charges a fee of $6 plus $17 an hour. Let x represent the number of hours the boat is rented and y represent the total cost of the rental. Write a system of equations to represent the problem situation. When is the cost of each rental company the same? Explain how you got your answer.