Final answer:
The distance between the points -2 and 1 on the number line is represented by the expression B. |-2 - 1|, which simplifies to |-3| and equals 3.
Step-by-step explanation:
The question asks to find the distance between two points on a number line, specifically between the points -2 and 1. The distance between two points can be calculated using the absolute value of the difference between the coordinates of the points. Thus, the expression |1 - (-2)| or |1 + 2| correctly represents the distance between the points -2 and 1.
Using the concept that distance is a scalar and has no negative values, which is reflected when we take the absolute value:
- A. |1 + (-2)| simplifies to |-1|, which equals 1.
- B. |-2 - 1| simplifies to |-3|, which equals 3. This is the correct distance between the points -2 and 1 on the number line.
Therefore, the correct answer is B. |-2 - 1|.