ĐK:x$\epsilon$$\left[ {0;2} \right]$&y$\geq$-2(*)
pt(1)$\Leftrightarrow$(x-1)$\left[ {(y+3)\sqrt{y+2}-(x+1)\sqrt{x}} \right]$=0
TH1:x=1
Từ pt(2)$\Rightarrow$y=$\frac{-31}{8}$(k t/m(*))
TH2:$(y+3)\sqrt{y+2}$=$(x+1)\sqrt{x}$
$\Leftrightarrow$$(\sqrt{y+2})^{3}$-$(\sqrt{x})^{3}$+$\sqrt{y+2}$-$\sqrt{x}$=0
$\Leftrightarrow$($\sqrt{y+2}-\sqrt{x}$)($y+2+\sqrt{x(y+2)}+x+1$)=0
$\Leftrightarrow$$\sqrt{y+2}$=$\sqrt{x}$(do(...)>0)
$\Rightarrow$x=y+2.Thế vào pt(2)$\Rightarrow$4$\sqrt{2-x}+2\sqrt{2x+4}$=$\sqrt{9x^{2}+16}$
$\Rightarrow$x=$\frac{4\sqrt{2}}{3}$$\Rightarrow$y=$\frac{4\sqrt{2}-6}{3}$(t/m)