Question

What is the number of diagonals in a (1) heptagon (2) octagona (3) polygon of 12 side

Answer 1

Step-by-step explanation:

i 14

ii 20

iii 54

formula is n×(n-3)/2

Answer 2

Answer:

If there are n-Sides of a convex polygon and n>3, then it has n (n-3) diagonals

2

1. A heptagon has = 7 ( 7 - 3 ) diagonals

2

= 49-21 = 28/2 = 14 diagonals.

2

2. A octagon has = 8 ( 8 - 3 ) diagonals

2

= 64-24 = 40/2 = 20 diagonals.

2

3. polygon of 12 side has = 12 ( 12 - 3 )

2

= 144-36 = 118/2 = 59 diagonals.

2