[tex]y = \frac{5}{ {x}^{2} - 5x} - \frac{x}{ \sqrt{7 - x} } \\ \displaystyle\bf\\\left \{ {{ {x}^{2} - 5x\neq0 } \atop {7 - x > 0 }} \right. \\ \displaystyle\bf\\\left \{ {{x(x - 5)\neq0} \atop { - x > - 7 \: \: | \times ( - 1) }} \right. \\ \displaystyle\bf\\\left \{ {{x\neq 0 \: \: and \: \: x\neq5} \atop {x < 7 }} \right. \\ \displaystyle\bf\\\left \{ {{x \: \epsilon \: ( - \propto; \: 0)U(0; \: 5)U(5; \: + \propto)} \atop {x \: \epsilon \: ( - \propto; \: 7)}} \right. \\ otvet \\ x \: \epsilon \: ( - \propto; \: 0)U(0; \: 5)U(5; \: 7)U(7; \: + \propto)[/tex]