1)
x + 2x
= 1x + 2x
= (1 + 2)x
= 3x
2)
2x - x
= 2x - 1x
= (2 - 1)x
= 1x
= x
3)
4x + 2x
= (4 + 2)x
= 6x
6x - 3x
= (6 - 3)x
5x + x
= 5x + 1x
= (5 + 1)x
[tex] [/tex]
