Question

equações de 2 grau incompletas
x²+x=0

Answer 1

$x^2+x =x(x+1)=0, \\ x=0 \\ x+1=0;x=-1.$
x=0 e -1

Answer 2

x² + x = 0
x (x + 1) = 0 

x = 0
x = x+1=0--->  x = -1

S=(-1; 0)