[tex]\it a)\ \ x=17 \Rightarrow ||17-4|-10|=3 \Rightarrow |13-10|=3 \Rightarrow 3=3\ (A)\\ \\ \\ ||x-4|-10|=3 \Rightarrow |x-4|-10=\pm3 \Rightarrow |x-4|-10\in\{-3,\ 3\}\Big|_{+10} \Rightarrow \\ \\ \Rightarrow |x-4|\in\{7,\ 13\} \Rightarrow x-4\in\{-13,\ -7,\ 7,\ 13\}_{+4} \Rightarrow x\in\{-9,\ -3,\ 11,\ 17\}[/tex]
