What is the inverse of y = 2x - 4?

To get the inverse of the function given by y=2x-4, we proceed as follows;

make x the subject;

y=2x-4

y+4=2x

thus;

x=1/2 (y+4)

next, we replace y by x and x by y^-1 to get our inverse, therefore we shall have the inverse as:

y^-1=1/2 (x+4)

this can be written as:

f^-1 (x) = 1/2 (x+4)