Another concrete rule I use to help my students is the Banana Rule. I noticed that my students often struggle with simplifying things like this(when we aren’t directly learning about it):

Sometimes they don’t realize that you can add them, but often times they realize they are like terms but end up messing with the exponents. To me, it’s really just a matter of how they are looking at it. My best attempt at getting my students to see this problem the way that I see it is by telling them that if everything in a term is the same except for the coefficient(1) is the same you can think of it as a banana. Therefore, the problem above is simply:

The banana rule, via Sweeny Math

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