(1) x²y²-6xy=-5,
(2) 3x+3y=10;
(1) xy(xy-6)=-5,
(2) 3(x+y)=10;
x+y=10/3;
y=10/3-x;
(1) x(10/3-x)(x(10/3-x)-6)=-5;
x(10/3-x)=t;
t(t-6)=-5;
t²-6t+5=0;
D=36-20=16;
t1=1;
t2=5;
x(10/3-x)=1; |*3
3x²-10x+3=0;
D=64;
x1=1/3
x2=3;
y1=10/3-1/3=3;
y2=10/3-3=1/3.
(1/3; 3), (3;1/3)
или
x(10/3-x)=5; |*3
3x²-10x+15=0;
D<0;<br>Нет корней.
Ответ: (1/3; 3), (3;1/3).