If a polygon has 8 sides, then the number of diagonals it has is:

8 16 20 24

20

The formula to find the number of diagonals is: D = n (n – 3)/2, where n stands for the number of sides According to the question, n= 8 D = 8 ( 8 – 3)/2 D = 8 (5)/2 D = 20