Area of a Trapezium by mrpettmaths

Area of a Trapezium by mrpettmaths
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2014-04-14 19:05
This example demonstrates how to calculate the area of a trapezium by transforming it into a parallelogram. Key concepts include trapezium, parallelogram, and area calculation. Commands used include Line, Polygon, Midpoint, Rotate, Intersect, Translate, etc. Suitable for middle school and above students to learn geometric transformations and area calculation.

GeoGebra Commands & Parameters

  1. Line(C, B) → b
  2. Line(A, b) → c
  3. Point(c) → D
  4. Polygon(A, B, C, D) → poly1, a_1, b_1, c_1, d
  5. Midpoint(c_1) → E
  6. Rotate(A, α, E) → A'
  7. Rotate(B, α, E) → B'
  8. Rotate(C, α, E) → C'
  9. Rotate(D, α, E) → D'
  10. Polygon(A', B', C', D') → poly1', a', b', c', d'
  11. OrthogonalLine(A, b_1) → e
  12. Intersect(e, b_1) → F
  13. Circle(B, (a * (d + b_1))) → f
  14. Line(B, b_1) → g
  15. Intersect(f, g) → G, H
  16. Vector(B, F) → u
  17. Vector(F, A) → v
  18. Translate(H, u) → H'
  19. Vector(H, H') → w
  20. Translate(H', v) → H''
  21. Vector(H', H'') → h
  22. Polygon(H, H', H'') → poly2, h'', h_1, h'
  23. Polygon(A, F, C, D) → poly3, a_2, f_1, c_2, d_1
  24. Segment(A, F) → i
  25. Circle(A, 0.5) → k
  26. Intersect(k, e, 2) → I
  27. Circle(F, 0.5) → p
  28. Intersect(p, b) → J, K
  29. Vector(F, H') → j
  30. Vector(F, A) → l
  31. Translate(K, l) → K'
  32. Vector(K, K') → m
  33. Translate(I, j) → I'
  34. Vector(I, I') → n
  35. Segment(K', K) → q
  36. Vector(A, D) → s
  37. Translate(I, s) → I'_1
  38. Vector(I, I'_1) → t
  39. Segment(I, I'_1) → r
  40. Segment(I'_1, I') → e_1
  41. Line(B, i) → g_1
  42. Circle(B, 0.5) → k_1
  43. Intersect(k_1, g_1, 2) → L
  44. Vector(B, C) → u_1
  45. Translate(L, u_1) → L'
  46. Vector(L, L') → v_1
  47. Segment(L, L') → i_1

AI Drawing Prompt Reference

Draw a trapezium and transform part of it by rotation and translation to form a parallelogram, demonstrating the area calculation of the trapezium. Key elements include the trapezium, parallelogram, rotated trapezium part, auxiliary lines, and circles. Start by drawing the trapezium, then rotate the midpoint of the top base to connect corresponding points to form the parallelogram. Use circles and lines to find key intersection points, and finally draw auxiliary line segments and arcs to complete the construction and area demonstration.
The prompt above was compiled from the original drawing commands and is for reference only.