The average of three numbers is x. if the first number is y and the second number is z, what is the third number?
a) (1/3)x-y-z
b) 3x-y-z
c) x-3y-3z
d)x+y+z over 3

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.

The areas of two similar triangles are 72dm2 and 50dm2. the sum of their perimeters is 226dm. what is the perimeter of each of these triangles?

Factor the polynomial expression x6 – x3 – 20