Решите систему уравнений

Решите задачу:

$\left\{\begin{array}{c}x^2+y^2=2.5xy\\x-y=0.25xy\end{array}\right\Rightarrow\left\{\begin{array}{c}(x-y)^2=2(0.25xy)\\x-y=0.25xy\end{array}\right\\(0.25xy)^2-2(0.25xy)=0\\\left\{\begin{array}{c}\left[\begin{array}{c}xy=0\\xy=8\end{array}\right\\x-y=0.25xy\end{array}\right\\\\1)\,x=0\Rightarrow y=0\,\,or\,\,y=0\Rightarrow x=0\\2)x={8\over y}\\{8\over y}-y=2\\{y^2+2y-8\over y}=0\\{(y+4)(y-2)\over y}=0\\y=-4\Rightarrow x=-2\,\,or\,\,y=2\Rightarrow x=4\\\\(-2;-4),\,(0;0),\,(4;2)$