Investigate the Angle Sum of a Quadrilateral

GeoGebra Commands & Parameters

1. Polygon(A, B, C, D) → poly1, a, b, c, d
2. Intersect(d, b) → F
3. Angle(B, A, F) → ρ
4. Angle(F, B, A) → κ
5. Angle(C, D, F) → ε
6. Angle(F, C, D) → ζ
7. Angle(D, F, C) → η
8. Angle(A, F, B) → θ
9. Angle(B, A, D) → α
10. Angle(C, B, A) → β
11. Angle(A, D, C) → γ
12. Angle(D, C, B) → δ
13. Segment(A, C) → e
14. Segment(D, B) → f
15. Intersect(e, f) → E
16. If(E ≟ E, "Concave", "Convex") → text3
17. PointIn(poly1) → Pointpoly1
18. Intersect(a, c) → G
19. Angle(B, F, A) → β2
20. Angle(C, F, D) → λ
21. Angle(D, C, F) → μ
22. Angle(F, D, C) → φ
23. Angle(F, A, B) → ξ
24. Angle(A, B, F) → α1
25. Angle(G, C, B) → ε1
26. Angle(C, B, G) → ε2
27. Angle(D, A, G) → ε3
28. Angle(G, D, A) → ε4
29. Angle(A, G, D) → ε5
30. Angle(B, G, C) → ε6
31. Angle(G, B, C) → γ1
32. Angle(B, C, G) → γ2
33. Angle(G, A, D) → γ3
34. Angle(A, D, G) → γ4
35. Angle(D, G, A) → γ5
36. Angle(C, G, B) → γ6
37. Angle(D, A, G) → θ1
38. Angle(G, D, A) → θ2
39. Angle(A, G, D) → θ3
40. Angle(G, C, B) → θ4
41. Angle(C, B, G) → θ5
42. Angle(B, G, C) → θ6
43. Angle(A, B, C) → ϕ1
44. Angle(B, C, D) → ϕ2
45. Angle(D, A, B) → ϕ4
46. Angle(C, D, A) → ϕ3