Answer:

Step-by-step explanation:
So we have the expression:

To simplify, simply combine the like terms. Therefore:

Further notes:
To understand why we can combine like terms in the first place, we just need to use the distributive property. So we have the expression:

Now, factor out a y from the three terms:

Do all the operations inside the parenthesis:

And we moved the y back to the front!
This is the same result as before. When combining like terms, this is what we're essentially doing but without doing the distributive property manually. I hope you understand a bit better on how and why we can combine like terms!