梯形面积计算 by Loizos Loizou

GeoGebra 命令及参数

1. Point(xAxis) → A
2. Point(xAxis) → B_3
3. Point(yAxis) → C
4. Segment(A, B_3) → B_1
5. Line(C, B_1) → b
6. Point(b) → B
7. Point(b) → E
8. Segment(B, E) → c
9. Segment(B, A) → d
10. Segment(E, B_3) → e
11. Midpoint(E, B_3) → F
12. Ray(B, F) → f
13. Ray(A, B_3) → g
14. Intersect(f, g) → G
15. Polygon(B, E, F) → poly1, f_1, d_1, e_1
16. Rotate(B, 45°, F) → D'
17. Rotate(F, 45°, F) → F'
18. Rotate(B, (-α), F') → Γ
19. Rotate(E, (-α), F') → E'
20. Rotate(F, (-α), F') → F'_1
21. Polygon(Γ, E', F'_1) → poly1', B_2, d'_1, e'
22. Polygon(B, F'_1, B_3, A) → poly2, d_2, f'_2, b_1, a_1
23. OrthogonalLine(B, g) → h
24. Intersect(b_1, h) → H
25. Segment(B, H) → υ