Open Middle: Equal Ratios and Equation Construction via Dilation
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This example demonstrates the “open middle” approach by constructing equal-ratio relationships inside a geometric configuration and turning those relationships into clear equation-style text. It focuses on key concepts such as equal ratios (proportional segments created by special points), linear-equation thinking for expressing relationships, and geometric similarity via dilation (scaling) that produces corresponding points. Construction-wise, it uses Polygon to build the base shapes, FractionText and Textfield to display ratio data as fractions, and If to control conditional display of information. Sequence and RandomElement help generate or iterate through point/ratio setups, making the theme reusable with varied parameters, while Dilate performs the geometric transformation establishing proportional correspondences. Mod and Text support systematic labeling and organization. The figure relies on multiple labeled points and polygon objects (including several poly* groups) together with auxiliary objects (f, g, h, i, etc.) for the interactive labeling and equation presentation. Suitable for middle to high school learners, especially for inquiry-based lessons connecting geometry reasoning with algebraic expression.
GeoGebra Commands & Parameters
Polygon(A0, B, 4) → poly0, f, g, h, i, A, CPolygon(A3, H, 4) → poly3, j, k, l, m, E, GPolygon(A7, P, 4) → poly7, n, p, q, r, I, KPolygon(A1, D, 4) → poly1, s, t, a, b, M, OPolygon(A6, N, 4) → poly6, c, d, e, f_1, Q, SPolygon(A2, H2, 4) → poly2, k_1, l_1, m_1, n_1, W, ZPolygon(A8, A8 + (2, 0), 4) → poly8, g_1, h_1, i_1, j_1, U, VPolygon(A9, T, 4) → poly9, p_1, q_1, r_1, s_1, A_1, B_1Polygon(A4, J, 4) → poly4, t_1, a_1, b_1, c_1, C_1, D_1Polygon(A5, L, 4) → poly5, d_1, e_1, f_2, g_2, E_1, F_1Polygon(K_1, L_1, 4) → poly10, l_2, m_2, n_2, p_2, M_1, N_1Polygon(O_1, P_1, 4) → poly12, q_2, r_2, s_2, t_2, Q_1, R_1Polygon(S_1, T_1, 4) → poly13, a_2, b_2, c_2, d_2, U_1, V_1Polygon(C_2, D_2, 4) → poly15, i_3, j_3, k_3, l_3, E_2, F_2Polygon(G_2, H_2, 4) → poly16, m_3, n_3, p_3, q_3, I_2, J_2Polygon(G_{3}, H_{3}, 4) → poly17, m_{4}, n_{4}, p_{4}, q_{4}, I_{3}, J_{3}Polygon(C_{3}, D_{3}, 4) → poly14, i_{4}, j_{4}, k_{4}, l_{4}, E_{3}, F_{3}FractionText(u) → text4If(aleft > aright, "Left side is bigger.", aleft < aright, "Right side is bigger", "Both sides are equal!") → text9Textfield(w) → InputBox1If(o_1 < 0, "less than", o_1 > 0, "greater than", o_1 ≟ 0, "equal to") → text12Sequence(i, i, 1, 80, 1) → l1Sequence(i, i, 1, 80, 1) → l2RandomElement(l1) → oRandomElement(l2) → w_1RandomElement(Sequence[i, i, -9, 9, 1]) → e_2Dilate(pic11, 1 / 4, A_2) → pic11'Dilate(pic12, 1 / 5, O_2) → pic12'Mod(Numerator[(i * 2)], Denominator[(i * 2)]) → j_2Mod(21, 7) → k_2Mod((10 * p14) + p17 - p12, p16) → i_2If(oddtest, "odd", "even") → text20
AI Drawing Prompt Reference
Draw a geometric figure with four parallelograms and one rhombus, demonstrating equal ratios through point positions and scaling transformations. First, draw four parallelograms, then generate a rhombus by adjusting point coordinates and applying scaling transformations. Finally, add fraction texts and conditional texts to display equal ratios and size comparisons.
The prompt above was compiled from the original drawing commands and is for reference only.