-5r + 8r + 5
We must combine like terms.
That basically just means that we add anything that has any like variables :)
In this case, our like terms are the variable "r."
So, we must add -5r to 8r
Think of this as if there were no "r" in there.
So, it looks like this : -5 + 8
What's -5 + 8?
It's 3! So, now we just need to add an 'r' after the 3.
So, -5r + 8r = 3r
Since we have no more like terms, our answer is :
3r + 5
~Hope I helped!~