Explanations:
Number lines are used to represent inequality expressions. The inequality signs are important to determine the orientation of the arrowheads on the number line.
For instance, the inequality < and ≤ show that the arrowhead is oriented towards the negative side of the number line while > and ≥ shows that the arrowhead is oriented towards the right
According to the question, we are to choose the number line that represents x ≥ 4. Since the inequality sign, in this case, is greater than, the arrow will be oriented towards the positive side of the number line.
Since 4 is included in the expression, the circle will be closed and placed on the positive 4 as shown:
This is the sketch of the number line that represents the inequality