Question

rezolvati sistemul de ecuatii
x+y=12
x*y=11

Answer 1

x=12-y
x*y=11

x=12-y
(12-y)*y=11

x=12-y
12y-y^2=11

x=12-y
(y-11)*(y-1)=0

x=12-y
y=11; y=1

x=1; x=11
y=11; y=1

S={(1;11)(11;1)}