A rectangular cutting board has a perimeter of 36 inches and an area of 80 square inches. What are the dimensions of the cutting board?

10 inches x 8 inches. 

You can get this by creating two equations.

xy = 80 and 2x + 2y = 36

Then you can solve the first one for either variable. Once you do that you can substitute it into the other equation and solve. You'll get a quadratic equation which will give you both parts of the answer.