三角形垂心构造

GeoGebra 命令及参数

1. Polygon(A, B, C) → poly1, c, a, b
2. OrthogonalLine(A, a) → f
3. OrthogonalLine(C, c) → g
4. OrthogonalLine(B, b) → h
5. Intersect(g, c) → D
6. Intersect(h, b) → E
7. Intersect(f, a) → F
8. Intersect(f, g) → G
9. Angle(G, E, A) → α
10. Angle(G, D, B) → β
11. Angle(G, F, C) → γ
12. Segment(B, E) → i
13. Segment(F, A) → j
14. Segment(D, C) → k
15. Line(C, B) → l
16. Line(A, B) → m
17. Intersect(f, l) → H
18. Intersect(g, m) → I
19. Angle(A, H, B) → δ
20. Angle(A, I, C) → ε