Triangle Area
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This example demonstrates calculating the area of a triangle through rotation and constructing polygons. Key mathematical concepts include area calculation, properties of equilateral triangles, rotation, and translation. It uses commands like Segment, Polygon, Rotate, Line, and Midpoint in GeoGebra. Suitable for middle school and above students to learn geometric construction and area calculation.
GeoGebra Commands & Parameters
Segment(A, Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]]) → jPolygon(A, B, C) → poly1, c, a, bPolygon(B, Midpoint[A, B], Midpoint[A, C], C) → poly2, b_1, d, e, c_1Rotate(Polygon[A, Intersect[OrthogonalLine[A, Line[Midpoint[A, B], Midpoint[A, C]]], Line[Midpoint[A, B], Midpoint[A, C]]], Midpoint[A, B]], α, Midpoint[A, B]) → poly3Rotate(Polygon[A, Intersect[OrthogonalLine[A, Line[Midpoint[A, B], Midpoint[A, C]]], Line[Midpoint[A, B], Midpoint[A, C]]], Midpoint[A, C]], (-α), Midpoint[A, C]) → poly4Segment(A, Intersect[OrthogonalLine[A, Line[B, C]], Line[Midpoint[A, B], Midpoint[A, C]]]) → mSegment(Intersect[OrthogonalLine[A, Line[B, C]], Line[Midpoint[A, B], Midpoint[A, C]]], Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]]) → nSegment(A, Midpoint[A, B]) → pSegment(A, Midpoint[A, C]) → qRotate(Polygon[A, Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], C], γ, Midpoint[A, C]) → poly5Rotate(Polygon[A, Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], B], (-γ), Midpoint[A, B]) → poly6Angle(Midpoint[A, C], Rotate[Intersect[OrthogonalLine[A, Line[Midpoint[A, B], Midpoint[A, C]]], Line[Midpoint[A, B], Midpoint[A, C]]], (-α), Midpoint[A, C]], Rotate[A, (-α), Midpoint[A, C]]) → ιAngle(Rotate[A, α, Midpoint[A, B]], Rotate[Intersect[OrthogonalLine[A, Line[Midpoint[A, B], Midpoint[A, C]]], Line[Midpoint[A, B], Midpoint[A, C]]], α, Midpoint[A, B]], Midpoint[A, B]) → ηAngle(Rotate[A, γ, Midpoint[A, C]], Rotate[Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], γ, Midpoint[A, C]], Rotate[C, γ, Midpoint[A, C]]) → θAngle(Rotate[B, (-γ), Midpoint[A, B]], Rotate[Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], (-γ), Midpoint[A, B]], Rotate[A, (-γ), Midpoint[A, B]]) → εAngle(C, B, Rotate[Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], (-γ), Midpoint[A, B]]) → δ_1Angle(Rotate[Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], γ, Midpoint[A, C]], C, B) → γ_1Angle(Rotate[Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], γ, Midpoint[A, C]], Rotate[Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], (-γ), Midpoint[A, B]], B) → ζAngle(Rotate[Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], (-γ), Midpoint[A, B]], Rotate[Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], γ, Midpoint[A, C]], C) → κRotate(Polygon[Midpoint[A, C], Intersect[OrthogonalLine[Midpoint[A, C], Line[B, C]], Line[B, C]], C], β, Midpoint[A, C]) → poly7Rotate(Polygon[Midpoint[A, B], Intersect[OrthogonalLine[Midpoint[A, B], Line[B, C]], Line[B, C]], B], (-β), Midpoint[A, B]) → poly8Polygon(Midpoint[A, B], A, Midpoint[A, C], Intersect[OrthogonalLine[Midpoint[A, C], Line[B, C]], Line[B, C]], Intersect[OrthogonalLine[Midpoint[A, B], Line[B, C]], Line[B, C]]) → poly9, l, s, a_1, d_1, e_1Angle(Midpoint[A, C], Intersect[OrthogonalLine[Midpoint[A, C], Line[B, C]], Line[B, C]], Intersect[OrthogonalLine[Midpoint[A, B], Line[B, C]], Line[B, C]]) → σAngle(Intersect[OrthogonalLine[Midpoint[A, C], Line[B, C]], Line[B, C]], Intersect[OrthogonalLine[Midpoint[A, B], Line[B, C]], Line[B, C]], Midpoint[A, B]) → τAngle(Rotate[C, β, Midpoint[A, C]], Rotate[Intersect[OrthogonalLine[Midpoint[A, C], Line[B, C]], Line[B, C]], β, Midpoint[A, C]], Midpoint[A, C]) → υAngle(Midpoint[A, B], Rotate[Intersect[OrthogonalLine[Midpoint[A, B], Line[B, C]], Line[B, C]], (-β), Midpoint[A, B]], Rotate[B, (-β), Midpoint[A, B]]) → ϕSegment(Intersect[OrthogonalLine[Midpoint[A, C], Line[B, C]], Line[B, C]], C) → f_1Segment(C, Midpoint[A, C]) → g_1Segment(Intersect[OrthogonalLine[Midpoint[A, C], Line[B, C]], Line[B, C]], Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]]) → h_1Segment(B, Midpoint[A, B]) → i_1Segment(B, Intersect[OrthogonalLine[Midpoint[A, B], Line[B, C]], Line[B, C]]) → j_1Segment(Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], Intersect[OrthogonalLine[Midpoint[A, B], Line[B, C]], Line[B, C]]) → k_1Angle(Rotate[Intersect[OrthogonalLine[A, Line[Midpoint[A, B], Midpoint[A, C]]], Line[Midpoint[A, B], Midpoint[A, C]]], (-α), Midpoint[A, C]], C, B) → χAngle(C, B, Rotate[Intersect[OrthogonalLine[A, Line[Midpoint[A, B], Midpoint[A, C]]], Line[Midpoint[A, B], Midpoint[A, C]]], α, Midpoint[A, B]]) → ψAngle(B, Midpoint[A, B], Rotate[Midpoint[A, B], (-α), Midpoint[A, C]]) → ρAngle(B, A, Rotate[Midpoint[B, C], β, Midpoint[A, C]]) → ωAngle(C, A, Rotate[Midpoint[B, C], β, Midpoint[A, B]]) → α_1Polygon(Rotate[A, δ, Midpoint[A, C]], Rotate[B, δ, Midpoint[A, C]], Rotate[C, δ, Midpoint[A, C]]) → poly1', r_1, s_1, t_1Polygon(B, Dilate[Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], g, A], C) → poly10, l_1, m_1, n_1Segment(Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], Dilate[Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], g, A]) → p_1Line(B, C) → q_1Angle(Rotate[B, δ, Midpoint[A, C]], A, Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]]) → λPolygon(A, Intersect[OrthogonalLine[A, Line[B, C]], Line[Midpoint[A, B], Midpoint[A, C]]], Midpoint[A, B]) → poly11, a_2, a_3, b_2Polygon(A, Intersect[OrthogonalLine[A, Line[B, C]], Line[Midpoint[A, B], Midpoint[A, C]]], Midpoint[A, C]) → poly12, c_2, a_4, d_2Polygon(Midpoint[A, C], Intersect[OrthogonalLine[Midpoint[A, C], Line[B, C]], Line[B, C]], C) → poly13, c_3, e_2, f_2Polygon(Midpoint[A, B], Intersect[OrthogonalLine[Midpoint[A, B], Line[B, C]], Line[B, C]], B) → poly14, b_3, h_2, i_2Rotate(A, (-γ), Midpoint[A, B]) → A'Rotate(Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], (-γ), Midpoint[A, B]) → DRotate(B, (-γ), Midpoint[A, B]) → B'Segment(A', D) → j_2Segment(D, B') → k_2Segment(B', A') → l_2Rotate(A, γ, Midpoint[A, C]) → A'_1Rotate(C, γ, Midpoint[A, C]) → C'Rotate(Intersect[OrthogonalLine[A, Line[B, C]], Line[B, C]], γ, Midpoint[A, C]) → ESegment(C', E) → m_2Segment(A'_1, C') → n_2Segment(E, A'_1) → p_2Rotate(A, α, Midpoint[A, B]) → A'_2Midpoint(A, B) → FRotate(Intersect[OrthogonalLine[A, Line[Midpoint[A, B], Midpoint[A, C]]], Line[Midpoint[A, B], Midpoint[A, C]]], α, Midpoint[A, B]) → GSegment(A'_2, G) → fSegment(G, F) → hSegment(F, A'_2) → iRotate(A, (-α), Midpoint[A, C]) → A'_3Midpoint(A, C) → HRotate(Intersect[OrthogonalLine[A, Line[Midpoint[A, B], Midpoint[A, C]]], Line[Midpoint[A, B], Midpoint[A, C]]], (-α), Midpoint[A, C]) → ISegment(I, A'_3) → kSegment(A'_3, H) → rSegment(H, I) → t