You add each number that is in the same position correlated to the box. Ex: 12+-3=9
X/7= -3
X= -21
Hope this helps!
Answer:

Step-by-step explanation:
I supposed that is a "n".
Steps as below:

Answer:
The Circle on the Top right doesn't belong since every other circle has a green quadrant, whereas on the other hand the circle on top right is missing the green quadrant
Hope this helps!