Denik777

Verified answer

(x-y)(x²+xy+y²)=7
7=9-xy(x-y)

(x-y)((x-y)²+3xy)=7
xy(x-y)=2
Обозначим xy=t, тогда x-y=2/t. Значит
(2/t)·(4/t²+3t)=7
2(4+3t³)=7t³
8+6t³=7t³
t³=8, t=2, откуда
xy=2, x-y=1
(y+1)y=2
y²+y-2=0
y1=-2; y2=1
x1=-1; x2=2
Ответ: (-1;-2), (2;1)