Question

x²+4x=0

Answer 1

Ta có : $x^2+4x=0$

$=>x(x+4)=0$

\(=>\left[{}\begin{matrix}x=0\\x+4=0\end{matrix}\right.\)

\(\left[{}\begin{matrix}x=0\\x=-4\end{matrix}\right.\)

Chúc bạn học tốt ^_^

Answer 2

\(x^2+4x=0\)

\(\Leftrightarrow x.x+x.4=0\)

\(\Leftrightarrow x\left(x+4\right)=0\)

\(\Leftrightarrow x=0\)

\(\Leftrightarrow x+4=0\Rightarrow x=-4\)