Question

$x^{2} +2x = 0$

Answer 1

x^2+2x=0
x(x+2)=0
x+2=0
x=-2

x=0
x=-2

Para 0:

0^2+2(0)=0
0=0

Para -2:

(-2)^2+2(-2)=0
4-4=0
0=0

Saludos

Answer 2

$x^{2} +2x = 0$

x(x+2) = 0

x = 0     x+2 = 0
             x = -2


CS = {-2; 0 }