Answer:

Step-by-step explanation:
Given

Required
Plot a new point that is 8 units down and also has the same x coordinate
Represent the new point with B'
In 
and 
This means that B' has an x coordinate of -6
Next, is to determine the y coordinate
If a point (x,y) is translated b units down, the new point is (x, y - b)
In this case:
The y coordinate of B is 0 and b = 8. So, the new y coordinate is: 0 - 8 = -8
So, we have:

See attachment