Answer:
1- a
2- b
3- c
4- d
Step-by-step explanation:
For any operation you have to separate the numbers from the unknown quantities (x, y) and then simplify them by solving them with quantities you are familiar with.
Example:
7x + 8 - 6 + 3x
7x + 3x + 8 - 6
you can only solve operations if they are both natural or algebraic numbers
10x + 2
Hope it was helpful ;)
