Idon't understand how to find the answer

What is the difference between regular convex and concave polygons

The difference between two numbers is one. three times the larger number minus two times the smaller number is 9. what are the two numbers

Val and tony get paid per project. val is paid a project fee of $44 plus $12 per hour. tony is paid a project fee of $35 plus $15 per hour. write an expression to represent how much a company will pay to hire both to work the same number of hours on a project.