Answer:
9.25
Step-by-step explanation:
∵ The coordinates of midpoint of a line segment having end points
and
are,
![((x_1+x_2)/(2),(y_1+y_2)/(2))](https://img.qammunity.org/2020/formulas/mathematics/high-school/poqwszeswe4wresxuec3qtcj5csywwzvro.png)
Given,
The coordinates of A are (-6, 13),
Coordinates of D are (2, 14),
If C is the midpoint of line segment AD,
Then the coordinates of C are,
![((-6+2)/(2), (13+14)/(2))](https://img.qammunity.org/2020/formulas/business/high-school/nafxexou8bet4dsl4kysfxrt0hlxach5lr.png)
![=((-4)/(2),(27)/(2))](https://img.qammunity.org/2020/formulas/business/high-school/z7ktvru2selct30nde81ayfvxmb1jw758u.png)
![=(-2, 13.5)](https://img.qammunity.org/2020/formulas/business/high-school/6fg9l3qfy1plw0qo0k9vp1gqpbmbwl0kmv.png)
Now, if B is the mid point of line segment AC,
Then the coordinates of B are,
![((-6-2)/(2),(13+13.5)/(2))](https://img.qammunity.org/2020/formulas/business/high-school/l45nyctap3u87a0qqvukmi3yjfb1shbssk.png)
![=((-8)/(2), (26.5)/(2))](https://img.qammunity.org/2020/formulas/business/high-school/q09o75q8zwdeq33l8cy9bmw48xzfh9r6el.png)
![=(-4, 13.25)](https://img.qammunity.org/2020/formulas/business/high-school/a2fekhdiiw5owwucxatu42fljq9rgoqiv4.png)
Hence, the sum of the coordinates of B = -4 + 13.25 = 9.25