0}} \right. \; \left \{ {{x\geq -9} \atop {x<4}} \right. \; \; \Rightarrow \; \; -9\leq x<4\\\\x\in [\, -9,4\, ) " alt=" \sqrt{x+9}+\frac{1}{\sqrt{4-x}}\\\\\left \{ {{x+9\geq 0} \atop {4-x>0}} \right. \; \left \{ {{x\geq -9} \atop {x<4}} \right. \; \; \Rightarrow \; \; -9\leq x<4\\\\x\in [\, -9,4\, ) " align="absmiddle" class="latex-formula">