How many diagonals does a octagon have?

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20 diagonals For any n-sided polygon, the formula for the number of diagonals is (n/2) x (n-3), so for an octagon it is (8/2) x (8-3) = 4 x 5 = 20.
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How many diagonals does an octagon have?

A polygon with n vertices has n*(n-3)/2 diagonals. . So an octagon has 8*5/2 = 20 diagonals. Of those 20 diagonals, 8are the principal diagonals, the ones joining a pair of o

How many diagonals does a octagon has?

20 diagonals For any n-sides polygon, the formula for the number of diagonals is (n/2) x (n-3), so for an octagon it is (8/2) x (8-3) = 4 x 5 = 20.

How many diagonals in a regular octagon?

20. And the fact that it is regular is irrelevant. 5 from each vertex. So 8 vertices would (you'd think) give 8*5 = 40. Except that you would then be counting each diagonal