Question

\(2x^2\)-72=0

Answer 1

\(2x^2-72=0\)

\(2x^2=72\)

\(\Rightarrow x^2=72:2=36\)

\(\Rightarrow\left\{{}\begin{matrix}x=6\\x=-6\end{matrix}\right.\)

Answer 2

Ta có: \(2x^2-72=0\)

\(\Rightarrow2x^2=72\)

\(\Rightarrow x^2=36\)

\(\Rightarrow x^2=6^2\)

\(\Rightarrow x=6\)

vậy \(x=6\)

Answer 3

\(2x^2-72=0\)

\(2x^2=72\)

\(x^2=36\)

\(x=\pm6\)

Answer 4

\(2x^2-72=0\)

\(\Leftrightarrow2x^2=72\)

\(\Leftrightarrow x^2=36\)

\(\Leftrightarrow x^2=6^2\)

\(\Leftrightarrow x=6\)