Question

Tìm x , biết

\(x^2-9x=0\)

Answer 1

\(x^2-9x=0\Leftrightarrow x\left(x-9\right)=0\Leftrightarrow\left\{{}\begin{matrix}x=0\\x-9=0\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}x=0\\x=9\end{matrix}\right.\) vậy \(x=0;x=9\)

Answer 2

\(x^2-9x=0\\ x\left(x-9\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=0\\x-9=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=9\end{matrix}\right.\)

Vậy \(\left[{}\begin{matrix}x=0\\x=9\end{matrix}\right.\)

Answer 3

Ta có: x² - 9x= x.( x - 9 )=0

=> x=0 hoặc x-9=0

=> x=0 hoặc x= 9

Answer 4

\(x^2-9x=0\)

\(\Leftrightarrow x.\left(x-9\right)=0\)

\(\Leftrightarrow\left\{{}\begin{matrix}x=0\\x-9=0\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=0\\x=9\end{matrix}\right.\)

Vậy x=0 hoặc x=9

Answer 5

\(x^2-9x=0\)

\(x.x-9x=0\)

\(\left(x-9\right).x=0\)

th1:\(x=0\)

th2:\(x-9=0\)

\(x=0+9\)

\(x=9\)

Vậy \(x=0\) hoặc \(x=9\)

Answer 6

\(x^2-9x=0\)

\(xx-9x=0\)

\(x.\left(x-9\right)\)\(=0\)

\(\Rightarrow\left\{{}\begin{matrix}x=0\\x-9=0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=0\\x=9\end{matrix}\right.\)

Vậy \(x=0\) hoặc \(x=9\)

Answer 7

\(x^2-9x=0\)

\(\Rightarrow x\left(x-9\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=0\\x-9=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=0\\x=9\end{matrix}\right.\)