Domain function help?

Math help?What is the implied domain of this function?

• In 2002, major league baseball signed a labor agreement with the players. In this agreement, any team whose payroll exceeds $128 million starting in 2005 will have to pay a luxury tax of 22.5% (for firsttime offenses). The linear function T ( p) = 0.225( p - 128) describes the luxury tax T of a team whose payroll is p (in millions of dollars). a. What is the implied domain of this function? Show me how to do it w/ the answer.

• Answer:

  This is the time where you use logic and math together, not just math. It should be clear that T(p) should not be negative, because you don't get money back for not exceeding the 128 million dollar threshold. This is still theoretical, in a sense that we know that the payroll of team has never exceeded ~250 million dollars, but since that information is not assumed to be known, then the domain is : p : [28, infinity) If this was given as math problem in your class, then the domain would be: (-infintiy, infinity), since this is a linear equation or a polynomial of degree one.