MathPlotAI Logo MathPlotAI

What Is Congruence (SAS)?

What Is Congruence (SAS)?
Loading the math board and drawing, please wait…
2019-04-18 19:43
TriangleTransformationGeometric Construction
This example demonstrates how to prove triangle congruence using the SAS (Side-Angle-Side) criterion. It involves core mathematical concepts such as triangle congruence, geometric construction, and transformations. Construction highlights include commands like Circle, Point, Segment, Rotate, Angle, Ray, Intersect, Min, Polygon, CircleSector, Mirror, Line, Dilate, Vector, Translate; and objects like a, b, α, A, c, B, f, d, B', β, g, C, h, i, e, k, D, E, poly1, c_1, a_1, b_1, p, F, A', B'_1, C', poly1', c', a', b'_1, p', A'_1, B'_2, f', A'_2, C'_1, i', j, G. Suitable for middle school and above students to learn and understand geometric proofs.

GeoGebra Commands & Parameters

  1. Circle(A, a) → c
  2. Point(c) → B
  3. Segment(A, B) → f
  4. Circle(A, b) → d
  5. Rotate(B, α, A) → B'
  6. Angle(B, A, B') → β
  7. Ray(A, B') → g
  8. Intersect(d, g, 1) → C
  9. Segment(B, C) → h
  10. Segment(A, C) → i
  11. Min(f, i) → e
  12. Circle(A, (0.25 * e)) → k
  13. Intersect(k, f) → D,
  14. Intersect(k, i) → E,
  15. Polygon(A, B, C) → poly1, c_1, a_1, b_1
  16. CircleSector(A, D, E) → p
  17. Mirror(A, h) → A'
  18. Mirror(B, h) → B'_1
  19. Mirror(C, h) → C'
  20. Polygon(A', B'_1, C') → poly1', c', a', b'_1
  21. Mirror(p, h) → p'
  22. Mirror(A, h) → A'_1
  23. Mirror(B, h) → B'_2
  24. Segment(A'_1, B'_2) → f'
  25. Mirror(A, h) → A'_2
  26. Mirror(C, h) → C'_1
  27. Segment(A'_2, C'_1) → i'
  28. Line(C, B) → j
  29. Point(j) → G
  30. Point(j) → H
  31. Ray(B, H) → l
  32. Ray(C, G) → m
  33. Circle(F, a) → q
  34. Point(q) → I
  35. Segment(F, I) → n
  36. Rotate(I, α, F) → I'
  37. Angle(I, F, I') → γ
  38. Circle(F, b) → r
  39. Ray(F, I') → s
  40. Intersect(r, s, 1) → J
  41. Segment(I, J) → t
  42. Segment(F, J) → f_1
  43. Dilate(B, If[0 < u ≤ 1, 1 - u, 0], I) → B'_3
  44. Vector(B, B'_3) → v
  45. Translate(A, v) → A'_3
  46. Translate(B, v) → B'_4
  47. Segment(A'_3, B'_4) → f'_1
  48. Line(B, n) → g_1
  49. Point(g_1) → K
  50. Angle(K, B, A) → δ
  51. Rotate(A'_3, If[1 < u ≤ 2, ((-(u - 1)) * δ), (-δ)], I) → L
  52. Rotate(B'_4, If[1 < u ≤ 2, ((-(u - 1)) * δ), (-δ)], I) → M
  53. Segment(L, M) → h_1
  54. Dilate(A, If[2 < u ≤ 3, 3 - u, 0], F) → A'_4
  55. Vector(A, A'_4) → w
  56. Translate(A, w) → A'_5
  57. Translate(C, w) → C'_2
  58. Segment(A'_5, C'_2) → i'_1
  59. Line(A, f_1) → i_1
  60. Point(i_1) → N
  61. Angle(N, A, C) → ε
  62. Rotate(A'_5, If[3 < u ≤ 4, ((-(u - 3)) * ε), (-ε)], F) → O
  63. Rotate(C'_2, If[3 < u ≤ 4, ((-(u - 3)) * ε), (-ε)], F) → P
  64. Segment(O, P) → j_1
  65. Translate(p, w) → p'_1
  66. Rotate(p'_1, If[3 < u ≤ 4, ((-(u - 3)) * ε), (-ε)], F) → d_1
  67. Dilate(B, If[4 < u ≤ 5, 5 - u, 0], I) → B'_5
  68. Vector(B, B'_5) → u_1
  69. Translate(A, u_1) → A'_6
  70. Translate(B, u_1) → B'_6
  71. Translate(C, u_1) → C'_3
  72. Polygon(A'_6, B'_6, C'_3) → poly1'_1, c'_3, a'_6, b'_6
  73. Line(B, t) → k_1
  74. Point(k_1) → Q
  75. Angle(Q, B, C) → ζ
  76. Rotate(A'_6, If[5 < u ≤ 6, ((-(u - 5)) * ε), (-ε)], I) → R
  77. Rotate(B'_6, If[5 < u ≤ 6, ((-(u - 5)) * ε), (-ε)], I) → S
  78. Rotate(C'_3, If[5 < u ≤ 6, ((-(u - 5)) * ε), (-ε)], I) → T
  79. Polygon(R, S, T) → poly2, t_1, r_1, s_1
  80. Segment(B, A) → l_1
  81. Segment(A, C) → m_1
  82. Segment(C, B) → n_1
  83. CircleSector(A, D, E) → e_1