Respuesta :

The answer would be (12x+9)
Add 6 and 3 to get 9, then add 5x and 7x to get 12x.
This would give you the final answer of (12x+9).
(6+5x)+(7x+3) combine like terms 5x+7x=12x 6+3=9 rewrite 9+12x
thats the simplest it can go to
Hope this helps have a nice nite!