Đk \(x+4\ne0\Leftrightarrow x\ne-4\)
\(\dfrac{x+4}{10}=\dfrac{10}{x+4}\Leftrightarrow\left(x+4\right)^2=10^2\)
\(\Leftrightarrow\left|x+4\right|=10\)
\(\Leftrightarrow\left[{}\begin{matrix}x+4=10\\x+4=-10\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=6\\x=-14\end{matrix}\right.\)
\(\dfrac{x+4}{10}=\dfrac{10}{x+4}\)
\(=>x+4.x+4=10.10\)
=> \(\left(x+4\right)^2=10^2\) hoặc = \(\left(-10\right)^2\)
=> \(x+4=10\) hoặc \(x+4=\left(-10\right)\)
\(x=10-4\) \(x=\left(-10\right)-4\)
\(x=6\) \(x=\left(-14\right)\)
Vậy x = 6 hoặc x = -14
