加减法练习：随机数与图形结合的互动教学

GeoGebra 命令及参数

1. Textfield(A1) → InputBox1
2. Random(-100, 100) → a
3. Random(-100, 100) → b
4. Random(-100, 100) → c
5. Random(-100, 100) → d
6. Random(-100, 100) → e
7. Random(-100, 100) → f
8. Random(-100, 100) → g
9. Random(-100, 100) → h
10. Random(1, 14) → i
11. Random(1, 14) → j
12. Element(list1, i, 1) → text1
13. Element(list2, j, 1) → text2
14. Polygon(A, B, C, D) → poly1, a_1, b_1, c_1, d_1
15. Point(a_1) → E
16. Point(c_1) → F
17. Point(c_1) → G
18. Point(a_1) → H
19. Polygon(E, F, G, H) → poly2, e_1, f_1, g_1, h_1
20. Point(d_1) → I
21. Point(b_1) → J
22. Polygon(I, J, B, A) → poly3, i_1, j_1, b_2, a_2
23. Point(b_1) → L
24. Polygon(I, K, L, J) → poly4, i_2, k_1, l, j_2
25. Polygon(K, D, C, L) → poly5, k_2, d_2, c_2, l_1
26. Corner(1) → S
27. Corner(2) → T
28. Corner(3) → U
29. Corner(4) → V
30. Polygon(S, T, U, V) → poly6, s, t, u, v
31. Element(list1, i, 2) → k
32. Textfield(A2) → InputBox2
33. Element(list2, j, 2) → m
34. SelectedIndex(list3) → o
35. If(k ≟ m, 4, If[k > m, 2, 3]) → p