Table of Contents
- 1 How many diagonal lines are in a 21 sided polygon?
- 2 How many diagonal can be drawn in a polygon?
- 3 How many lines are there in a polygon having 189 diagonals?
- 4 How many diagonals drawn from a vertex does a 21 sided polygon have?
- 5 How many diagonals are there in a polygon of 10 sides?
- 6 How many diagonals are in a N Gon?
- 7 How to calculate the number of diagonals in a 20 sided polygon?
- 8 Is the side of a polygon always a straight line?
- 9 Where do the diagonals go in a concave polygon?
How many diagonal lines are in a 21 sided polygon?
Polygons
| Sides | Diagonals |
|---|---|
| 19 | 152 |
| 20 | 170 |
| 21 | 189 |
| 22 | 209 |
How many diagonal can be drawn in a polygon?
The number of diagonals in a polygon that can be drawn from any vertex in a polygon is three less than the number of sides. To find the total number of diagonals in a polygon, multiply the number of diagonals per vertex (n – 3) by the number of vertices, n, and divide by 2 (otherwise each diagonal is counted twice).
How many diagonals can be drawn in a polygon of N sides?
The number of diagonals in a polygon = n(n-3)/2, where n is the number of polygon sides. For a convex n-sided polygon, there are n vertices, and from each vertex you can draw n-3 diagonals, so the total number of diagonals that can be drawn is n(n-3).
How many lines are there in a polygon having 189 diagonals?
So as the no. of sides cannot be negative so the number of sides of a polygon having 189 diagonals has 21 sides.
How many diagonals drawn from a vertex does a 21 sided polygon have?
Diagonals of one vertex equals to: 21 (number of vertex) – 1 (itself) – 2 (sides with vertices next to it). So the answer should be: That’s different from 170 obtained above.
How many diagonal lines can be drawn in a pentagon?
five diagonals
A pentagon has five diagonals (lines drawn between the corners). You can trace over all of the diagonals without lifting your pencil and without going over any more than once. Try it. Can the same thing be done with a hexagon (6 sides) or with a heptagon (7 sides)?
How many diagonals are there in a polygon of 10 sides?
35 diagonals
How many diagonals of a regular decagon (a 10 sided polygon) are not parallel to any of the sides (AMC12)? A decagon has (10 2) – 10 = 35 diagonals. Each pair of opposing sides has three diagonals which are parallel to them, so 5*3 = 15 of the diagonals are parallel to a side.
How many diagonals are in a N Gon?
Answer. To find the total number of diagonals in a polygon, multiply the number of diagonals per vertex (n – 3) by the number of vertices, n, and divide by 2 (otherwise each diagonal is counted twice)….Solved Examples.
| Polygon Name | Number of Sides | Number of Diagonals |
|---|---|---|
| Hexagon | 6 | 9 |
| Heptagon | 7 | 14 |
How many lines of symmetry does a 20 gon have?
20
Icosagon/Line of symmetry
How to calculate the number of diagonals in a 20 sided polygon?
In a 20-sided polygon, one vertex does not send any diagonals. Find out how many diagonals does that 20-sided polygon contain. In a 20-sided polygon, the total diagonals are = 20 (20-3)/2 = 170. But, since one vertex does not send any diagonals, the diagonals by that vertex needs to be subtracted from the total number of diagonals.
Is the side of a polygon always a straight line?
It should be noted the sides of a polygon are always a straight line. In a polygon, the diagonal is the line segment that joins two non-adjacent vertices. An interesting fact about the diagonals of a polygon is that in concave polygons, at least one diagonal is actually outside the polygon.
How to find the number of diagonals in an octagon?
A octagon has 20 diagonals. Define the formula. The formula to find the number of diagonals of a polygon is n (n-3)/2 where “n” equals the number of sides of the polygon. [8]
Where do the diagonals go in a concave polygon?
You can also run a line from the bottom hinge corner up to the top, opposite corner. Those are the only two diagonals possible. In concave, simple polygons, the diagonals may go outside the polygon, crossing sides and partly lying in the shape’s exterior. They are still diagonals.