$1.\begin{cases}x^2-y^2+2\sqrt[3]{x^4}+\sqrt[3]{x^2}+y^3= 2y\sqrt{y-1}(x+\sqrt[3]{x})\\ x^4+\sqrt{x^3+x^2+1}=x(y-1)^3+1 \end{cases}$$2.\begin{cases}\sqrt{x+\sqrt{y}}+3\sqrt{y}-7\sqrt{x}=4 \\ (2\sqrt{y}-1)^2-y\sqrt{xy}= (2\sqrt{x}-1)^2-x\sqrt{xy}\end{cases}$