At maximum speed, an airplane travels 2400 miles against the wind in 6 hours. flying with the wind, the plane can travel the same distance in 5 hours.
let x be the maximum speed of the plane and y be the speed of the wind.
what is the speed of the plane with no wind?

Arestaurant offers delivery for their pizzas. the total cost the customer pays is the price of the pizzas, plus a delivery fee. one customer pays $23 to have 2 pizzas delivered. another customer pays $59 for 6 pizzas. how many pizzas are delivered to a customer who pays $86?