The coordinates are ordered pairs with the x value listed first.
The change in x position is, 8-7=1
The change in y position is, 3-(-2)=5
Since the midpoint is halfway between A and B, the change will stay the same,
So, for B,
x is 7-1=6
y is -2-5=-7
The coordinnates of B is (6,-7)
