平行四边形对角相等

GeoGebra 命令及参数

1. Line(C, A) → g
2. Line(B, g) → i
3. Line(A, B) → f
4. Line(C, f) → h
5. Intersect(i, h) → D
6. Polygon(A, B, D, C) → q1, a, b, d, c
7. Segment(C, B) → j
8. Point(j) → E
9. Midpoint(C, E) → F
10. Segment(D, A) → k
11. Line(F, k) → l
12. Intersect(d, l) → G
13. Intersect(l, c) → H
14. Polygon(E, H, G) → t1, g_1, e, h_1
15. Polygon(G, D, B, A, H) → poly1, g_2, d_1, b_1, a_1, h_2
16. Angle(G, E, H) → α
17. Angle(A, C, D) → β
18. Point(k) → I
19. Midpoint(O, I) → J
20. Line(J, j) → m
21. Intersect(m, d_1) → K
22. Intersect(d, m) → L
23. Polygon(L, I, K) → t2, k_1, l_1, i_1
24. Angle(C, D, B) → γ
25. Angle(B, A, C) → δ
26. Angle(D, B, A) → ε
27. Angle(L, I, K) → ζ
28. Polygon(L, K, B, A, C) → poly2, l_2, k_2, b_2, a_2, c_1
29. Polygon(L, D, K) → t3, k_3, l_3, d_2
30. Angle(L, I, K) → η
31. Angle(G, E, H) → θ
32. Polygon(G, H, C) → t4, c_2, g_3, h_3