+) \(\frac{-3}{4}-x=\frac{2}{5}\)
=> \(-x=\frac{2}{5}+\frac{3}{4}\)
=> \(-x=\frac{23}{20}\)
=> \(x=\frac{-23}{20}\)
Vậy \(x=\frac{-23}{20}\)
+) \(\frac{-4}{x}=\frac{x}{-16}\)
=> \(x.x=-4.\left(-16\right)\)
=> \(x^2=64\)
=> \(x=\sqrt{64}=8\)
hoặc \(x=-\sqrt{64}=-8\)
Vậy \(x=8\) hoặc \(x=-8\)
\(\frac{-3}{4}-x=\frac{2}{5}\)
\(\Rightarrow x=\frac{-3}{4}-\frac{2}{5}=\frac{-15}{20}-\frac{8}{20}=-\frac{23}{20}\)
Vậy: \(x=-\frac{23}{20}\)
\(\frac{-4}{x}=\frac{x}{-16}\)
\(\Rightarrow x^2=-4.-16=64\)
\(\Rightarrow x=\sqrt{64}=\pm8\)
Vậy: \(x=\pm8\)