(3х+у)^2 +2(x-y)^2=96
3x+y=2(x-y)
3x+y=a
(x-y)=b
a^2+2b^2=96 4b^2+2b^2=96 6b^2=96 b1=4 b2=-4
a=2b
a1=2b1=8
a2=2b2=-8
3x+y=a1 3x+y=8 3(4+y)+y=8 y=-1
(x-y)=b1 (x-y)=4 x=5 (5;-1)
3x+y=a2 3x+y=-8 3(-4+y)+y=-8 y=1
x-y=b2 x-y=-4 x=-4+y x=3 (3;1)
Ответ: (5;-1) (3;1)