Answer:
x + y = 680
5x + 7y = 3914
Explanation:
Let the amount of students who purchased tickets equal x.
Let the amount of adults who purchased tickets equal y.
If you add the amount of adults and students, you get the total amount of people:
x + y = 680
Also, to find the amount students spent on tickets, you multiply the ticket price by the amount of students to get 5x. And to find the amount adults spent on tickets, you multiply the ticket price by the amount of adults to get 7y. By adding the two amount, you get the total amount of money:
5x + 7y = 3914
These are the two equations:
x + y = 680
5x + 7y = 3914