{xy(x-y)=6
{xy+(x-y)=-5
(x-y)=-5-(xy)
xy(x-y)=6
xy•(-5-(xy))=6
xy=t
t(-5-t)=6
-5t-t²-6=0
t²+5t+6=0
D=25-24=2
t=(-5±1)/2
t1=-3;t2=-2
1)xy=-3
x=-3/y
-3-3/y-y=-5
-3y-3-y²+5y=0;y≠0
y²-2y+3=0
D=4-12=-8
y€∅
2){xy=-2
{xy+(x-y)=-5
-2-2/y-y=-5
-2y-2-y²+5y=0
y²-3y+2=0
D=9-8=1
y=(3±1)/2
y1=2;y2=1
x1=-1;y2=-2
(-1;2);(1;-2)