Question

Let f(x) = 9x − 4.5. Find the value of f(2).

Answer 1

plug in 2 wherever you see x

Answer 2

plug 2 in the equation where u see x and solve for it :p

Answer 3

f(2) is the same as saying x=2

only thing you have to do is substitute on the formula
9(2) − 4.5 = 13.5