Answer
Choice B
Work Step by Step
Since $|x|\ge c$ implies $x\ge c \text{ or } x\le-c,$ then the the given inequality, $
|2x+1|\ge3
,$ is equivalent to
\begin{array}{l}\require{cancel}
2x+1\ge3 \text{ or } 2x+1\le-3
.\end{array}
Hence, $\text{
Choice B
.}$
