For each problem, write a system of equations to model each problem. Then, solve the problem.
7. The difference of two numbers is 18. The sum of the same two numbers is 4. Find the two numbers.
8. The theater guild sold 180 tickets for their first Broadway show. Each adult ticket cost $16 and each student ticket
cost $10. The total ticket sales for the show were $2478. How many adult tickets and student tickets were sold?