To determine the set and write the a notation and interval rotation:
Let the set of all values on the number line be x
[tex]\begin{gathered} \mleft\lbrace x\text{I }x\text{ }\leq\text{ -}\infty\mright]\}\text{ meaning} \\ The\text{ set of all x values on the number line that are less than and equal to -13} \end{gathered}[/tex]Therefore the set buider is represented below:
[tex]\mleft\lbrace x\text{ I }x\leq-\infty\mright\rbrace\mleft\lbrace-\infty\leq x\leq-13\mright\rbrace[/tex]