-8.5 + 5 = -3.5
0.75 + (-0.75) = -1.5
-3.5 + 0.5 = -3
-11 + 5.6 = -5.4
-5.2 + (-2) = -7.2
-0.75 + (-3) = -3.75
-3 + 0.5 = -2.5
-0.5 + 1.5 = 1
-0.75 + 0.75 = 0
