Why is Penrose triangle impossible?

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Tags

1. #rules
2. #undecidable
3. #geometry
4. #exist
5. #figure
6. #possibly
7. #violated
8. #impossible
9. #penrose
10. #object
11. #triangle
12. #would
13. #could
14. #depicts
15. #order
16. #euclidean
17. #because
18. #which