Đáp án:
$ A=(-\infty;-1) \cup \left(\dfrac{13}{3};+\infty\right).$
Giải thích các bước giải:
$A=\{x \in \mathbb{R}|-3x+5|>8\}\\ |-3x+5|>8\\ \Leftrightarrow \left[\begin{array}{l} -3x+5>8\\ -3x+5<-8\end{array} \right.\\ \Leftrightarrow \left[\begin{array}{l} -3x>3\\ -3x<-13\end{array} \right.\\ \Leftrightarrow \left[\begin{array}{l} 3x<-3\\ 3x>13\end{array} \right.\\ \Leftrightarrow \left[\begin{array}{l} x<-1\\ x>\dfrac{13}{3}\end{array} \right.\\ \Rightarrow A=(-\infty;-1) \cup \left(\dfrac{13}{3};+\infty\right).$