-3x = 21
Divide -3 from both sides and you get x = -7
1/3x = 6
Divide 1/3 from both sides and you get x = 18
-1/2x = -7
Divide -1/2 from both sides and you get x = 14 (you get a positive answer from 2 negatives)
Dividing 1/3 is just multiplying by 3, and dividing -1/2 is just multiplying by -2
