the answer ............

Answer:
f^-1(x) = ( x + 6 )/4
Step-by-step explanation:
f(x) is the same as...y = 4x + 6....and then try to make x the subject of formula
y + 6 = 4x
x = (y + 6)/4....then when writing f^-1(x)...replace y with x
f^-1(x) = ( x + 6 )/4