All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info
Home > Shapes
Puzzles involving various geometric shapes, in a flat plane and in three-dimensional space.
Sub-Categories (All Problem Categories)
> Geometry (1)
A pentagram is typically constructed by taking the diagonals of a regular pentagon.

This common pentagram has five angles measured at the vertices, each of which equals 36 degrees. In total all five angles sum to 180 degrees.

Generalize to make an irregular pentagram by taking the diagonals of a convex irregular pentagon.

This irregular pentagram also has five angles measured at the five vertices. Show that the sum of these five angles equals 180 degrees.
(No Solution Yet, 1 Comments) Submitted on 2021-02-24 by Brian Smith   
Page 1 of 33   next >>    
Difficulty: 4 of 53D geometry |
Posted on 2021-01-22 by Danish Ahmed Khan (No Solution Yet, 0 Comments)
Difficulty: 3 of 5Gold-in pyramid | Rating: 5.00
Posted on 2020-10-06 by Jer (Solution Posted, 7 Comments)
Difficulty: 3 of 5Tetrahedral angles |
Posted on 2020-09-17 by Danish Ahmed Khan (No Solution Yet, 0 Comments)
Difficulty: 4 of 5Square to Cone Conversion |
Posted on 2020-09-12 by Larry (No Solution Yet, 1 Comments)
Difficulty: 4 of 5Sphere parts |
Posted on 2020-09-09 by Danish Ahmed Khan (No Solution Yet, 1 Comments)
Difficulty: 5 of 5Extreme revolving cuboid | Rating: 2.00
Posted on 2020-08-28 by Danish Ahmed Khan (No Solution Yet, 4 Comments)
Difficulty: 4 of 5Cosine cups |
Posted on 2020-08-07 by Danish Ahmed Khan (No Solution Yet, 5 Comments)
Difficulty: 3 of 5Tilted drum |
Posted on 2020-06-12 by Danish Ahmed Khan (No Solution Yet, 2 Comments)
Difficulty: 3 of 5Reflection Triangle | Rating: 3.50
Posted on 2020-01-24 by Danish Ahmed Khan (No Solution Yet, 5 Comments)
Difficulty: 3 of 5Maximal Rectangle |
Posted on 2019-12-30 by Danish Ahmed Khan (No Solution Yet, 4 Comments)
Difficulty: 4 of 5Heptagonal Triangle | Rating: 3.00
Posted on 2019-12-27 by Danish Ahmed Khan (No Solution Yet, 4 Comments)
Difficulty: 3 of 5Three Squares make a Triangle | Rating: 3.00
Posted on 2019-12-23 by Larry (No Solution Yet, 3 Comments)
Difficulty: 3 of 5Triangle rotation |
Posted on 2019-10-02 by Danish Ahmed Khan (No Solution Yet, 5 Comments)
Difficulty: 3 of 5Area of central locus |
Posted on 2019-09-19 by Danish Ahmed Khan (No Solution Yet, 1 Comments)
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (3)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2021 by Animus Pactum Consulting. All rights reserved. Privacy Information