For the probability of two dice summing to nine, you can have:
Each outcome has , as the dice are fair.
So the probability is
For the probability of two dice summing to five, you can have:
Which gives the same probability as for the sum of the dice to 9.
Because dice rolls are independent, the probability of rolling a 9 with 2 die followed by rolling 5 with 2 die
For binomial expansions,
The 5th term will be (binomial expansion formula).