6p+3p as a equivalent expression

Answer 1

What is common between the two terms? p, of course. 6p is saying 6 times p and 3p is saying 3 times p. If we divide p from both terms, we end up with...

p(6 + 3)

Yeah, we could go further and say p(9) = 9p, but we aren't asked to go that far.

Answer 2

These are called "like" terms, both are a number multiplied by the variable p.

So in one bucket there are 6 p's, and in another bucket there are 3 p's. If you pour all of the p's together into a new bucket you will have 9 p's in the new bucket.

The equivalent expression is 9p