-1 because -3x+1=2 (4 total spaces) so,
2+1 is 3
you have life numbers and x values separate.
divide positive 3 by negative 3 to get -1.
check your answer by plugging it in
-1*-3 is 3
so - 3+1 world be 4 which is where the 2 is on the number line because it goes into negatives
answer is x= -1
The same reason that you need to have the same amount of weight on both sides of something. It is a part of laws of math, you cant have an unbalanced chemical equation the same way you cant have an unbalanced math equation. You have to look at it like its a physical thing that has properties, not just ink on a paper.
Answer:
A. 
B doesn't work because only positive 7 would be a possible value. Negative numbers cubed get a negative answer.
