How do you find the inverse of $f (x) = \frac{3 x + 4}{5}$ $f(x) = (3x + 4) / 5$ ?

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Answer 1 · 2017-07-14T06:23:26

You have $y = \frac{3 x + 4}{5}$ $y=(3x+4)/5$

To find $f^{- 1} (x)$ $f^(-1)(x)$ you switch the $x$ $x$ s and $y$ $y$ s.

$y = \frac{3 x + 4}{5}$ $y=(3x+4)/5$ becomes $x = \frac{3 y + 4}{5}$ $x=(3y+4)/5$

$5 x = \frac{5 (3 y + 4)}{5} = 3 y + 4$ $5x=(5(3y+4))/5=3y+4$

$5 x - 4 = 3 y + 4 - 4 = 3 y$ $5x-4=3y+4-4=3y$

$\frac{5 x - 4}{3} = \frac{3 y}{3} = y$ $(5x-4)/3=(3y)/3=y$

How do you find the inverse of f(x)=3x+45f(x) = (3x + 4) / 5?