y + 1.2y + 1.2z

2.4yz

1.3y + 1.2z

*1.2y2 + 1.2z

2.2y + 1.2z

* = it is 1.2y with a little 2 up and to the side of it.

For the answer to the question above. Are you asking on how to add y + 1.2y + 1.2z? The answer is just

2.2y + 1.2z

you just have to add the common terms since you have both (1) y and 1.2 y same as y (1+1.2) = 2.2y

since there's no z term, it's just 1.2z so you get

2.2y + 1.2z

This is just a simple problem of addition on algebra.