Question

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

Answer 1

${x}^{2} + x = 0 \\ x(x + 1) = 0 \\ x = 0 \: o u \: x + 1 = 0 \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: x = - 1$


S = {-1, 0}