Inverse function:
The only one that has an inverse that is a function is the third option because is a linear function (bijective)
y=1/3x-3/4
First, solve for x:
Add 3/4 to both sides:
y+3/4 = 1/3x-3/4+3/4
y+3/4 = 1/3x
Multiply both sides by 3
(y+3/4) 3 = 1/3x (3)
3y+ 9/4 = x
F^-1(y) = 3y+ 9/4