\[\boxed{\text{294.}\text{\ }\text{ОК\ ГДЗ\ -\ домашка\ на\ 5}}\]
\[\textbf{а)}\ \frac{x - 5}{x + 6} < 0\]
\[(x - 5)(x + 6) < 0\]
\[(x + 6)(x - 5) < 0\]
\[x \in ( - 6;5).\]
\[\textbf{б)}\ \frac{1,4 - x}{x + 3,8} < 0\]
\[(1,4 - x)(x + 3,8) < 0\]
\[(x + 3,8)(x - 1,4) > 0\]
\[x \in ( - \infty;\ - 3,8) \cup (1,4;\ + \infty).\]
\[\textbf{в)}\ \frac{2x}{x - 1,6} > 0\]
\[2x(x - 1,6) > 0\]
\[x \in ( - \infty;0) \cup (1,6;\ + \infty).\]
\[\textbf{г)}\ \frac{5x - 1,5}{x - 4} > 0\]
\[(5x - 1,5)(x - 4) > 0\]
\[5 \cdot (x - 0,3)(x - 4) > 0\]
\[x \in ( - \infty;0,3) \cup (4;\ + \infty).\]