C is the answer i believe
-4x +4 = -3x + 31
4 - 31 = -3x + 4x
-27 = x
D answer is 9 , 24/8 = 3
3x3=9
Left to right. Whatever comes first (multiplication or division) you do. This is all part of the PEMDAS/Order of operations.
Hopefully I solved your problem! :)