Question

Only people with working brain can answer.

Nah, not you.​

Answer 1

Answer:

Step-by-step explanation:

Answer 2

Interesting!

You take n sided polygon, it has n vertices. You join 3 at a time to form a triangle, so you find how many different ways can you join 3 points, that is, nC3

i.e. n!/(n-3)! (3!) = n (n-1) (n-2)/6