已知实数$x$、$y$满足$\sqrt{x-3}+y^2-4y+4=0$，求代数式$\frac{x^2-y^2}{\mathit{xy}}·\frac{1}{x^2-2\mathit{xy}+y^2}÷\frac{x}{x^{2}y-x{y}^2}$的值．