What is the inverse of the function 1/9x+2

f − 1 ( x ) = 9 x − 18  

Explanation:

To find the inverse or  

f − 1 ( x )  of a function we solve the equation for  x

So in this example, we can start by subtracting  

2  from both sides:  y − 2 = 1 9 x + 2 − 2  

Next we multiply  

9  to each side to isolate the variable  x  9 ( y − 2 ) = 1 x 9 ⋅ 9 9 y − 18 = x

Since the function of a line is written in terms of  y  we can simply switch  x  and y  and rewrite the equation to get:  y = 9 x− 18  or  f − 1 ( x ) = 9 x − 18