Question

x²-4=0

Answer 1

\(x^2-4=0\)

\(\Rightarrow x^2=4\)

\(\Rightarrow x^2=2^2\)

\(\Rightarrow x=2\)

Vậy \(x=2\)

Answer 2

x^{2 _} 4=0

x² = 4

=> x² = +_ 2²

=> x=+_2

Answer 3

\(x^2-4=0\)

\(\Rightarrow\left(x-2\right)\left(x+2\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x-2=0\\x+2=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=2\\x=-2\end{matrix}\right.\)

Vậy......................................