Answer:
-3
Step-by-step explanation:
y = 2/3x +6
Exchange x and y
x = 2/3y +6
Solve for y
x-6 = 2/3y+6-6
x-6 = 2/3 y
Multiply each side by 3/2
3/2(x-6) = 3/2*2/3y
3/2x - 9 = y
The inverse is 3/2x -9
f^-1(x) = 3/2x-9
Let x = 4
f^-1(4) = 3/2(4)-9
= 6-9
= -3
