SOLUTION: nCn-2=10. solve to find 'n' different?

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Question 847247: nCn-2=10. solve to find 'n' different?
Answer by swincher4391(1107) About Me  (Show Source):
You can put this solution on YOUR website!
nC(n-2) = n%21%2F%28n-2%29%21%282%21%29+=+10

So we have that %28n%2A%28n-1%29%29%2F2+=+10
n%2A%28n-1%29+=+20
n%5E2+-n+=+20
n%5E2+-n+-20+=+0
%28n-5%29%28n%2B4%29+=+0
n = 5.