$(-\infty, -3] \cup (4, \infty)$
Work Step by Step
The left portion of this graph "starts" at negative infinity and ends at, and includes, $-3$, therefore the left side reads: $(-\infty, -3]$. The right portion of this graph starts at, but does not include, $4$; and "ends" at positive infinity. The right side reads: $(4, \infty)$. These two portions of the graph are united with a $\cup$ symbol.