18sqrt(x)
I'm assuming that 3(sqrt(x))5 is equal to 15sqrt(x). If that is the case, just perform the multiplication within each term and treat the sqrt(x) as a variable when you add the all together. It is okay because they are like terms.
I THINK it is 23 i hope it helps
Answer:
4
Step-by-step explanation:
Answer:
9(c^7)
Step-by-step explanation:

c^-4 is equal to 1/(c^4), so 1/(c^(-4)) is c^4.