what is the function of f(x)=3x-1.5

Question

f(x) = 3X - 1.5

Answer 1

Student,

 

If you are asking for a DESCRIPTION of what the given function represents, it is a straight line with a slope of +3 crossing the y-axis at (0,-1.5).  Other than this, there is not much more we can tell you.  Is part of the question missing, as Thomas hinted?

Answer 2

It is already a function! Done! Did you leave off part of the question, such as what is the function at 5, or what is the inverse?