Question 309361
Let f(x) = y

y = 3x - 4

Switch x and y.

x = 3y - 4

Add 4 to both sides.

x + 4 = 3y

Divide both sides by 3.

(x + 4)/3 = y

Replace y with the inverse notation f^-1 (x).

(x + 4)/3 = f^-1 (x)