3b - b
3m + 5m - 5n + 10m
x + x + x - x - x - x
3a + 4b - 2a - b
a + a + a + a
2xy + 3y - 2x + 4xy + 5x -8y
2x + 3x + 4x + 5x
m + n + m + n + m + n
6xy - 5y + 3x
a + 3b
0
14x
4a
3m + 3n
2b
-2n + 15m
