Use Pascal’s triangle to solve for the value of n: 2(n C 3) = n+4 C 7

Question

Use Pascal’s triangle to solve for the value of n:  2(n C 3) = n+4 C 7

ganeshie8 · Answer

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ganeshie8 · Answer

Notice that the entries along a diagonal will have a fixed $k$ value in binomial coefficient $\binom{n}{k}$

ganeshie8 · Answer

Easy to eyeball the answer : 

$\binom{4}{3}=4$

 $\binom{8}{7}=8$

anonymous · Answer

lol I am still confused. I already knew n = 4 because I solved this problem before, but I cant for the life of me remember how I got it

ganeshie8 · Answer

you must be knowing that the rows are numbered starting with "n=0"
look at the second pic, what are the "row numbers" corresponding to the blue circled values  ?

anonymous · Answer

Lol I think im just going to forget this problem. I never liked Pascal's trinagle lmao

anonymous · Answer

If given multiple choice I figure this out easily, otherwise I will never need to boggle my mind over this

ganeshie8 · Answer

takes time to get used to pascal triangle and appreciate its beauty

anonymous · Answer

Dont worry though I will not give up so easily, I just dont feel like dealing with this now. Going to get ready to watch the big fight, thank you so much for taking your time to help me :)

ganeshie8 · Answer

np have good time