Question

write formula for calculating of digonals in a polygon with no of side​

Answer 1

$\huge\mathcal\pink{ANSWER:-}$

Number of Diagonals = n(n-3)/2

In other words, an n-sided polygon has n-vertices which can be joined with each other in nC2 ways. Now by subtracting n with nC2 ways, the formula obtained is n(n-3)/2. For example, in a hexagon, the total sides are 6. So, the total diagonals will be 6(6-3)/2 = 9.

Answer 2

-}ANSWER:−

Number of Diagonals = n(n-3)/2

In other words, an n-sided polygon has n-vertices which can be joined with each other in nC2 ways. Now by subtracting n with nC2 ways, the formula obtained is n(n-3)/2. For example, in a hexagon, the total sides are 6. So, the total diagonals will be 6(6-3)/2 = 9.