28 of them
A 30 sided polygon contains 28 triangles.
cocokragon
Oh, dude, a 14-sided polygon? That's like, a lot of sides. So, the number of lines of symmetry for a regular polygon is equal to the number of sides if it's an even number, and half the number of sides if it's an odd number. So, for a 14-sided polygon, since it's an even number, it would have 14 lines of symmetry.
20 diagonals in Octagan. For n-sided polygon, no of diagonals = (n choose 2 ) - n = 8C2 - 8 = 28 - 8 = 20
28 of them
A 30 sided polygon contains 28 triangles.
28
cocokragon
icosikaioctagon
28 We can check this using smaller prisims, with a triangular prism (3-sided) there are 6 vertices. WIth a rectangular prism (4-sided), there are 8 vertices. The number of vertices in a prism is always twice the number of sides.
12.4567890
A 4-sided polygon has 2 diagonals. A 5-sided polygon, 5. 6-sided, 9. By induction, an n-sided polygon has 'n*(n-3)/2' diagonals. "n" is how many sides a shape has. so, (7)*(7-3)/2 now we have, 7*4/2 so, 28/2 = 14 Therefore, a 7-sided polygon would have 14 diagonals.
A 28-sided shape is called an icosikaioctagon. The prefix "icosi" denotes 20 sides, and the suffix "-octagon" denotes 8 sides, combining to form the name for this polygon. It is a type of polygon known as a polygon with 28 sides.
The sum of the interior angles of a polygon with n sides is 180o × (n - 2), consequently the sum of the interior angles of a 28-sided polygon is 4680o (180o × 26).
A 28 sided polygon is called an Icosikaioctagon This link should help: http://www.math.com/tables/geometry/polygons.htm
For an n-sided regular polygon, the sum of the interior angles is equal to 180 x (n - 2). In the case of a 28-sided polygon, this would be 180 x (28 - 2) = 180 x 26 = 4680 degrees.