How do i find a formula for the inverse if this is one to one

Good evening Guest!

How do i find a formula for the inverse

if this is one to one x - 10 /x + 4

y = x - $\frac{10}{x}$ + 4

Inverse

x = y - $\frac{10}{y}$ + 4

xy = y² - 10 + 4y

y² - 10 + 4y - xy = 0

y² + (4 - x) y - 10 = 0

Quadratic formula

$y = {-b \pm \sqrt{b^2-4ac} \over 2a}$

a = 1   b = (4 - x)    c = - 10

$y = {x-4 \pm \sqrt{(4-x)^2+40} \over 2}$  

This is the inverse function.

Greetings asinus :- )

  !