Question

Write the inverse function for the function, ƒ(x) = 1/2x + 4. Then, find the value of ƒ -1(4). Type your answers in the box

Answer 1

F(x) = (1/2)x + 4
Plug y in for f(x).
y = (1/2)x + 4
Swap x and y.
x = (1/2)y + 4
Solve the equation for y =.
Subtract 4 from both sides.
x - 4 = (1/2)y
Multiply each term 2.
2x - 8 = y
Plug f^-1(x) in for y.
f^-1(x) = 2x - 8

f^-1(4) = 2(4) - 8
f^-1(4) = 0