# Math Help - Inverse of a function

1. ## Inverse of a function

Hello - I need help with the following problem. I was asked to find the inverse of: f(x) = 7x+3 over 8

If I’m doing this correctly, I would first replace f(x) with “y”, then I switched “y” and “x”. I believe my next step would be to multiply both sides by 8, correct? So I think that would give me 8x = 56y+24? From here I’m stuck because I’m forgetting a process I’ve already learned. I know I need to get y by itself but how?

Your help is greatly appreciated.

2. $y = \frac{7x+3}{8}$

swap variables ...

$x = \frac{7y+3}{8}$

multiply both sides by 8 ...

$8x = 7y+3$

solve for y to finish it.

3. My answer would be 8x-3 over 7 = Y
?

4. so ... how can you check the result?