Find the inverse of the following function y = 7-3x
I got:
y-7 = -3x
y-7/3 = x
-x-7/3 = y
End.
You need to divide through by $\displaystyle -3$
$\displaystyle y = 7-3x$ swap $\displaystyle x$ and $\displaystyle y$, then make $\displaystyle y$ the subject
$\displaystyle x = 7-3y$
$\displaystyle x - 7= -3y$
$\displaystyle \frac{x - 7}{-3}= y$
$\displaystyle y=\frac{x - 7}{-3}$
$\displaystyle y=\frac{-x }{3}+\frac{ 7}{3}$