Answer
$\dfrac {y\cos x-e^{y}}{xe^{y}-\sin x}$
Work Step by Step
$xe^{y}=y\sin x\Rightarrow \dfrac {d}{dx}\left( xe^{y}\right) =\dfrac {d}{dx}\left( y\sin x\right) \Rightarrow e^{y}+xe^{y}\dfrac {dy}{dx}=\dfrac {dy}{dx}\sin x+y\cos x\Rightarrow \dfrac {dy}{dx}=\dfrac {y\cos x-e^{y}}{xe^{y}-\sin x}$