Can anybody help me please

Answer:
Which grade is this from?
Step-by-step explanation:
maybe i can figure it out. :D
Answer:
A= -3, B= 3, C= -2
Step-by-step explanation:
If "y" is -x minus 3, then y= 3. That's box a.
If "y" is zero, then 3-3= 0. Box b is 3.
-(-1)-3= 1-3= -2 = x. Box c is -2