Polygon Diagonals from Sides
Calculate the number of diagonals in a polygon from the number of sides.
Table of Contents
20 Number of Sides =
170 Diagonal Count
Representative value from the Polygon Diagonals from Sides reference table.
Reference Values
Browse 20 reference values with individual detail pages for quick lookup.
Polygon Diagonals from Sides
Calculate the number of diagonals in a polygon from the number of sides.
Calculated Result
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Reference Table
Use this complete table for quick lookup and internal linking to specific value pages.
| Number of Sides | Diagonals |
|---|---|
| 3 Number of Sides | 0 Diagonal Count |
| 4 Number of Sides | 2 Diagonal Count |
| 5 Number of Sides | 5 Diagonal Count |
| 6 Number of Sides | 9 Diagonal Count |
| 7 Number of Sides | 14 Diagonal Count |
| 8 Number of Sides | 20 Diagonal Count |
| 9 Number of Sides | 27 Diagonal Count |
| 10 Number of Sides | 35 Diagonal Count |
| 12 Number of Sides | 54 Diagonal Count |
| 15 Number of Sides | 90 Diagonal Count |
| 20 Number of Sides | 170 Diagonal Count |
| 24 Number of Sides | 252 Diagonal Count |
| 30 Number of Sides | 405 Diagonal Count |
| 40 Number of Sides | 740 Diagonal Count |
| 50 Number of Sides | 1,175 Diagonal Count |
| 60 Number of Sides | 1,710 Diagonal Count |
| 100 Number of Sides | 4,850 Diagonal Count |
| 180 Number of Sides | 15,930 Diagonal Count |
| 360 Number of Sides | 64,260 Diagonal Count |
| 720 Number of Sides | 258,120 Diagonal Count |
Frequently Asked Questions
Common questions about Polygon Diagonals from Sides, formulas, and typical use cases.
What does the Polygon Diagonals from Sides calculator do?
It helps with counting diagonals in polygon geometry and combinatorics-style shape problems.
What formula does the Polygon Diagonals from Sides calculator use?
Polygon diagonals = n × (n - 3) / 2.
What inputs are valid?
The number of sides must be an integer greater than or equal to 3.
When would I use this?
counting diagonals in polygon geometry and combinatorics-style shape problems
Methodology and Review
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