You just need to match the terms that are the same. Let's look at number one.
2x^2 + 4x +1 + 3x^2 +6x +5 the matching parts:
the 2x^2 and the 3x^2 go together. That means you can combine them here they are positive so you add them.
The 4x and the 6x go together they both only have an x with them. They are both positive so you can add them together.
Last you have a 1 and a 5. These are matching so you can combine them too. They are both positive too so just add them together.
So your final answer would be 5x^2 + 10x + 6. Does that make sense?
