conbaodn

1/$\left\{\begin{matrix} & 2x^{3}-9y^{3}=(x-y)(2xy+3)\\ & x^2-xy+y^3=3 \end{matrix}\right.$

2/$\left\{\begin{matrix} & \sqrt{2x-3}=(y^2+2014)(5-y)+\sqrt{y}\\ & y(y-x+3)=3x+3 \end{matrix}\right.$

\3/$\left\{\begin{matrix} x(x+y+1)=3 & \\ (x+y)^2-\frac{5}{x^2}+1=0 & \end{matrix}\right.$

4/$\left\{\begin{matrix}\sqrt{x+2}=y+1 & \\ y(y+x+1)=2x(x-1) & \end{matrix}\right.$