Answer:
28
Step-by-step explanation:
So in order to get this answer you want to use the combination formula which is 
Now you want to use the numbers given to you in the problem which is ₈C₂ and plug those into the equation
so your going to have something looking like this
now if you have a calculator nearby and you plug in ₈C₂ your going to get 28 which is the answer.
hope this somewhat helps.
X=1, x=-7 would be the correct answer.
<h3>
Answer: 680 different combinations</h3>
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Explanation:
If order mattered, then we'd have 17*16*15 = 4080 different permutations. Notice how I started with 17 and counted down 1 at a a time until I had 3 slots to fill. We count down by 1 because each time we pick someone, we can't pick them again.
So we have 4080 different ways to pick 3 people if order mattered. But again order doesn't matter. All that counts is the group itself rather than the individual or how they rank. There are 3*2*1 = 6 ways to order any group of three people, which means there are 4080/6 = 680 different combinations possible.
An alternative is to use the nCr formula with n = 17 and r = 3. That formula is

where the exclamation marks indicate factorials
Answer:
Should not be rejected.
Step-by-step explanation: