Which expression is equivalent to -1/3 (6x + 15) -3

If f(x)= 3x+6 which of the following is the inverse of f(x)

The level of co2 emissions, f(x), in metric tons, from the town of fairfax x years after they started recording is shown in the table below. x 2 4 6 8 10 f(x) 26,460 29,172.15 32,162.29 35,458.93 39,093.47 select the true statement.

Ineed me i stuck and i don’t want to get it wrong