| 5x + 2x | 7x |
| 11y - 6y | 5y |
| 11y - 6y - y | 4y |
| 7x + 6x - x | 12x |
| 6z - 13z | -7z |
| 7x - 8x | -x |
| -3y - 3y | -6y |
| -4z + 4z | 0 |
| x + y + 2x | 3x + y |
| 3y - 3z + 2y | 5y - 3z |
| -4x + 5x - 9y - y | x -10y |
| -y + 2y + 6x - 9x | y - 3x |
| 11 + 8y - 2y - 2x | 11 + 6y - 2x |
| 5x + 2x | 7x |
| 11y - 6y | 5y |
| 11y - 6y - y | 4y |
| 7x + 6x - x | 12x |
| 6z - 13z | -7z |
| 7x - 8x | -x |
| -3y - 3y | -6y |
| -4z + 4z | 0 |
| x + y + 2x | 3x + y |
| 3y - 3z + 2y | 5y - 3z |
| -4x + 5x - 9y - y | x -10y |
| -y + 2y + 6x - 9x | y - 3x |
| 11 + 8y - 2y - 2x | 11 + 6y - 2x |