Question

Add.
(x^5-9)+(x^5+9)

Answer 1

So, in this case, the parenthesis can just be ignored, because they dont do anything (if u want u can distribute a "1" to actually break them.
x^5-9+x^5+9 combine likes
(x^5+x^5)+(9-9)
(2x^5)+(0)
2x^5