Answer:
a. B
b. 4
c. BD
Explanation:
a. Point A is at -7; point D is at +1. The distance between these points is ...
1 -(-7) = 8
The midpoint will be 8/2 = 4 units from either end so will be at ...
A +4 = -7 +4 = -3
or
D -4 = 1 -4 = -3
The point located at -3 is point B, the midpoint of AD.
__
b. Having done the above calculations, we know that segment AB is 4 units long.
__
c. We also know that segment BD is 4 units long. That is because the midpoint divides a segment into two equal parts.