I'm a little rusty in complex algebra I was wondering how i would go about solving this equation for $\displaystyle w$

$\displaystyle \frac{w+i}{w-i} = \frac{-1+i}{1-i}\left(\frac{z+1}{z-1}\right)$

The correct answer being $\displaystyle w = \frac{i-z}{i+z}$