Answer:
now i dont know if this is the thing your asking but a negative plus a negative is a positive.
This is easy to calculate as the line is straight vertical. There are 7 units in between the two end points of the line segment, so dividing this by 2 will give you the units from an end point to the mid point. 7 ÷ 2 = 3.5. Subtracting 3.5 from the higher y-value or adding it to the lower y-value gets you (5, 0.5).
