If f (x) = 2x + 5 what is f - 1 (x) ?

f^-1 (x) = 1/2x - 5/2

Step-by-step explanation:

To find the inverse of a function, exchange x and y and then solve for y

y = 2x+5

Exchange x and y

x = 2y+5

Solve for y

Subtract 5 from each

x-5 = 2y+5-5

x-5 = 2y

Divide by 2

(x-5) / 2 = 2y/2

1/2x - 5/2 = y

f^-1 (x) = 1/2x - 5/2