Find the Missing Coordinate

Question 1:

A is the coordinate (-3,-9). If the midpoint of A and B is (-5.5,-9.5), find B.
(-8,-10)

Question 2:

A is the coordinate (0,1). If the midpoint of A and B is (-1.5,-2.5), find B.
(-3,-6)

Question 3:

A is the coordinate (1,8) and B is (7,4), find the midpoint.
(4,6)

Question 4:

A is the coordinate (1,7) and B is (7,5), find the midpoint.
(4,6)

Question 5:

A is the coordinate (4,4) and B is (2,6), find the midpoint.
(3,5)

Question 6:

A is the coordinate (6,-5). If the midpoint of A and B is (0,-3), find B.
(-6,-1)