# User Forum

Subject :IMO    Class : Class 7

Find the sum of the number of diagonals drawn from one vertex of a polygon of 13 sides and the number of diagonals drawn from the adjacent vertex of that vertex of the same polygon.

A11
B26
C22
D19

the answer should be 20 as from each vertex there should be n-3 or 10 diagonals so from 2 vertices there should be 20 diagonals

## Ans 1:

Class : Class 7
If the answer is 22 then the polygon should be 14 sided.

Class : Class 8

Class : Class 9

Class : Class 8

## Ans 5:

Class : Class 7
Number of diagonals drawn from polygon of n sides is n-3Thus, answer should be 2(13-3) = 2*10 = 20

## Ans 6:

Class : Class 9
ANSWER MUST BE 20 SINCE FORMULA IS N-3 SO FOR ONE VERTICE IT IS 10 SO TWO WILL BE 20

## Ans 7:

Class : Class 8
it should be 20 because the formula for number of diagonals from a vertices is n-3, so for one vertice is 10 diagonals so two is gonna be 20

Class : Class 8
ans is 20!!

Class : Class 7
It should be 20

Class : Class 10

Class : Class 8

## Ans 12:

Class : Class 7
Really it will be 20

Class : Class 8