3+5x-2
4x+4x-x
3b+3a+3c-b-a-c
-3x+8-7x
4x+4y+4x+4y
-5x+10x
5h-6x-8f-3h-4x-6f
4x+5x
6x-2x+4x+12-4
5x+1
7x
8x+8y
2h-2x-2f
-10x+8
8x+8
5x
9x
2b+2a+2c
