构造平行四边形：几何作图与面积探究

GeoGebra 命令及参数

1. Line(A, B) → f
2. Line(C_1, f) → g_2
3. Point(g_2) → D
4. Line(A, D) → h_2
5. Line(B, h_2) → i_2
6. Intersect(g_2, i_2) → C
7. Polygon(A, D, C, B) → poly1, a, d, c, b
8. Intersect(d, c) → F
9. Line(G, H) → j_1
10. Line(J, j_1) → k_2
11. Circle(G, Distance[G, H]) → e
12. Circle(J, Distance[G, H]) → p
13. Intersect(p, k_2, 2) → I
14. Polygon(G, J, I, H) → poly2, g, j, i, h
15. Line(K, L) → l_2
16. Circle(N, Distance[K, L]) → q_2
17. Line(K, N) → m_2
18. Circle(L, Distance[K, N]) → r_2
19. Intersect(q_2, r_2, 2) → M
20. Polygon(K, N, M, L) → poly3, k, n, m, l
21. Rotate(O, 50°, P) → O'
22. Angle(O, P, O') → α
23. Rotate(P, (-(130°)), O) → P'
24. Angle(P', O, P) → β
25. Rotate(P, 130°, O') → P'_1
26. Angle(P, O', P'_1) → γ
27. Rotate(O, (-(50°)), P') → O'_1
28. Angle(O'_1, P', O) → δ
29. Polygon(P, O', P', O) → poly4, w, o', p', o
30. Segment(Q, S) → s_1
31. Midpoint(s_1) → Z
32. Line(R, Z) → t_1
33. Circle(Z, Distance[Z, R]) → c_1
34. Intersect(c_1, t_1, 2) → T
35. Polygon(Q, T, S, R) → poly5, t, s, r, q