Question

Find the inverse of the following function:

f(x) = 3x + 12

I don't think I worked this problem off correctly...I am suppose to find the inverse of the function
Is this the correct way to work this problem?

y= 3x + 12
x= 3y + 12
3y = x - 12
f-1(x) = x - 12/3

Answer 1

You would divide everything by 3 leaving you with f-1(x)= x/3 - 4

Answer 2

see the correct and easy way is like this :

y=3x +12

now get x in terms of y
3x =y-12
or x= (y-12)/3
now replace x with y and vice versa
so you will get :
y= (x-12)/3
or f-1(x)= x/3 - 4

this should be the answer