\[y = \frac{2x}{(1 - x)(x + 5)}\]
\[(1 - x)(x + 5) \neq 0\]
\[x \neq 1;\ \ x \neq - 5.\]
\[D(y) = ( - \infty; - 5) \cup ( - 5;1) \cup (1; + \infty).\]