Jack and Diane were saving money to go to a rock n roll concert. They need at least $750 in order to go if you
count their gas, hotel, food, concert tickets, and souvenir money. Jack plays gigs at the local Tastee Freez and
Diane car hops. Jack earns $50 per night that he plays, and Diane earns $25 each night she works. The number
of nights Diane is scheduled to work is no more than four times the number of nights Jack is scheduled to play.
Diane will work at least 10 times before the concert.
Write a set of constraints to model the problem, with x representing the number of nights Jack worked and y
representing the number of nights Diane worked.