Please help these are the questions

i think the answer to the second to last would be r exponent 4

Step-by-step explanation:

4r

10x + 20y + 20

Step-by-step explanation:

We have two questions that have many terms, and we are asked to combine those like terms.

Like terms are when two number end with the same symbol, this can be an exponent, variable, e.t.c.

Let's take a look at r + r + r + r.

These are all like terms therefore we can add them together.

r + r + r + r

4r

Onto the next we have 16x + 20y - 6x + 23 - 3

Take a look at what was said earlier and put it in, you can only combine like terms or variables that end with the same letter.

Therefore :

16x - 6x

20y

23 - 3

10x + 20y + 20