On a number​ line, suppose the coordinate of A is​ 0, and AR = 16 What are the possible coordinates of the midpoint of ​AR?

Answer 1

Draw a line number. AR start at origin (A coordinate is 0) but we do not know if AR is oriented to the right of A (or in the positive direction) or is oriented to the left of A (or in the negative direction).

There for there are two possibilities:

1. A has coordinate 0 and R has coordinate +16, in this case middle point has coordinate 8
2. A has coordinate 0 and R has coordinate -16, in this case middle point has coordinate -8