Isosceles Triangle and Two Congruent Segments

Isosceles Triangle and Two Congruent Segments
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2017-03-22 09:52
This example illustrates the relationship between an isosceles triangle and two congruent segments. Key mathematical concepts include the properties of isosceles triangles and the definition of congruent segments. Constructed using GeoGebra commands such as Rotate, Angle, Ray, Segment, Intersect, Circle, Point, Distance, Polygon, Min, CircleSector, Dilate, Vector, Translate, Line, it is suitable for students at the junior high school level and above for geometric construction.

GeoGebra Commands & Parameters

  1. Rotate(B, (a * π / 180), A) → B'
  2. Angle(B, A, B') → α
  3. Ray(A, B') → f
  4. Segment(A, B) → g
  5. Rotate(A, (-((a * π / 180))), B) → A'
  6. Angle(A', B, A) → β
  7. Ray(B, A') → h
  8. Intersect(f, h) → C
  9. Segment(A, C) → i
  10. Segment(B, C) → j
  11. Circle(B, 1) → c
  12. Ray(A, B) → k
  13. Intersect(c, k, 2) → D
  14. Ray(B, D) → l
  15. Circle(C, 1) → d
  16. Ray(A, C) → m
  17. Intersect(d, m, 2) → F
  18. Ray(C, F) → n
  19. Circle(B, 1) → p
  20. Ray(C, B) → q
  21. Intersect(p, q, 2) → H
  22. Ray(B, H) → r
  23. Point(n) → E
  24. Circle(B, Distance[A, E]) → e
  25. Intersect(e, r, 1) → G
  26. Segment(E, G) → s
  27. Intersect(l, s) → I
  28. Distance(E, I) → distanceEI
  29. Distance(I, G) → distanceIG
  30. Polygon(A, B, C) → poly1, c_1, a_1, b
  31. Polygon(B, I, E, C) → poly2, b_1, i_1, e_1, c_2
  32. Polygon(B, I, G) → poly3, g_1, b_2, i_2
  33. Min(i, g) → o
  34. Circle(A, (0.35 * o)) → t
  35. Intersect(t, i, 1) → J
  36. Intersect(t, g) → K,
  37. Rotate(K, If[0 < u ≤ 1, (u * α), α], A) → K'
  38. CircleSector(A, K, K') → d_1
  39. CircleSector(A, K, J) → f_1
  40. Dilate(A, If[2 < u ≤ 3, 3 - u, 0], B) → A'_1
  41. Vector(A, A'_1) → v
  42. Translate(f_1, v) → h_1
  43. Rotate(h_1, If[3 < u ≤ 4, ((u - 3) * (π - α)), π - α], B) → k_1
  44. Dilate(E, If[4 < u ≤ 5, 5 - u, 0], I) → E'
  45. Segment(E, E') → j_1
  46. Rotate(E, If[5 < u ≤ 6, ((u - 5) * π), π], I) → E'_1
  47. Rotate(E', If[5 < u ≤ 6, ((u - 5) * π), π], I) → E''
  48. Segment(E'_1, E'') → l_1
  49. Line(A, E) → m_1
  50. Line(E'_1, m_1) → n_1
  51. Point(n_1) → L
  52. Dilate(A, If[7 < u ≤ 8, 8 - u, 0], E) → A'_2
  53. Segment(A, A'_2) → p_1
  54. Angle(B, E'_1, L) → γ
  55. Dilate(E, If[8 < u ≤ 9, 9 - u, 0], E'_1) → E'_2
  56. Vector(E, E'_2) → w
  57. Translate(A, w) → A'_3
  58. Translate(A'_2, w) → M
  59. Segment(A'_3, M) → q_1
  60. Rotate(A'_3, If[9 < u ≤ 10, ((-(u - 9)) * γ), (-γ)], E'_1) → N
  61. Rotate(M, If[9 < u ≤ 10, ((-(u - 9)) * γ), (-γ)], E'_1) → M'
  62. Segment(N, M') → r_1

AI Drawing Prompt Reference

Draw an isosceles triangle ABC with AB=AC. Draw a unit circle centered at B, intersecting the extension of AB at D and the extension of AC at E. Draw a unit circle centered at C, intersecting the extension of CA at F. Connect DE, intersecting BC at I. With I as the center and IE as the radius, draw a circle intersecting BC at G. Connect EG, intersecting BC at J. With B as the center and BJ as the radius, draw a circle intersecting DE at K, then rotate K to get K'. With A as the center and AK as the radius, draw an arc d1, and with AK' as the radius, draw an arc f1.
The prompt above was compiled from the original drawing commands and is for reference only.