Răspuns :
x+y=0
y=x^2
=>x+x^2=0=>x(1+x)=0=> x=0 sau 1+x=0=>x=-1
Cazul 1: x=0=> y=0^2=> y=0
Cazul 2: x=-1=> y=(-1)^2=> y=1
S= {(0;0) , (-1;1)}
y=x^2
=>x+x^2=0=>x(1+x)=0=> x=0 sau 1+x=0=>x=-1
Cazul 1: x=0=> y=0^2=> y=0
Cazul 2: x=-1=> y=(-1)^2=> y=1
S= {(0;0) , (-1;1)}