Answer:
Well, for (D), the answer would be 32.
Step-by-step explanation:
Because, 20 +12 =32. And 32 - 12 = 20. With the other ones that add, its the same way. You can just for example, if its -5 + b = -40, you can just go 5 - 40= which equals 35. Which should give you 40 if you add 35 and 5 together.
