\(\frac{x}{4}=9x\)
\(\Leftrightarrow36x=x\)
\(\Leftrightarrow36x-x=0\)
\(\Leftrightarrow35x=0\)
\(\Leftrightarrow x=0\)
mình nhầm 9/x nha
\(\frac{x}{4}=\frac{9}{x}\)
\(\Leftrightarrow x^2=36\)
\(\Leftrightarrow\orbr{\begin{cases}x=6\\x=-6\end{cases}}\)
Vậy x=6; x=-6
\(\frac{x}{4}=9x\)
\(\Leftrightarrow x:4=9x\)
\(\Leftrightarrow x.\frac{1}{4}=9x\)
\(\Leftrightarrow x.\frac{1}{4}-9x=0\)
\(\Leftrightarrow x\left(\frac{1}{4}-9\right)=0\)
\(\Leftrightarrow x=0\)
