I need help please what’s the answer?

The terms combine into 9x + 17

Step-by-step explanation:

What you need to realise here is that the brackets don't serve any real purpose, as there's no operation being done on their contents as a whole.  With that in mind we can simply drop the brackets and group like terms:

(4x + 8) + (5x + 9)

= 4x + 8 + 5x + 9

= 4x + 5x + 8 + 9

= 9x + 17

So the terms combine into 9x + 17