Proof Without Words: Isosceles Triangle Base Midpoint Property
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This example demonstrates the property of the midpoint of the base of an isosceles triangle by dragging points. It proves that the distances from the midpoint to the two legs of the isosceles triangle are equal. By constructing midpoints, mirrors, semicircles, and other geometric objects, the property is visually demonstrated. Suitable for junior high school geometry.
GeoGebra Commands & Parameters
Intersect(xAxis, yAxis) → APoint(xAxis) → BRay(A, B) → aPoint(a) → CMirror(C, A) → C'Semicircle(C, C') → cIntersect(c, yAxis) → D,CircleArc(A, D, C) → dPoint(d) → ESegment(C, E) → bSegment(E, C') → eSegment(C', C) → fPolygon(C', C, 4) → poly1, g, h, i, j, F, GPolygon(C, E, 4) → poly2, k, l, m, n, H, IPolygon(E, C', 4) → poly3, p, q, r, s, J, KMidpoint(E, J) → LOrthogonalLine(L, i) → tOrthogonalLine(L, t) → a_1Intersect(a_1, s) → MIntersect(t, r) → NIntersect(a_1, q) → OIntersect(t, e) → PPolygon(M, L, N, K) → poly4, m_1, l_1, n_1, k_1Polygon(L, N, J, O) → poly5, l_2, n_2, j_1, oPolygon(L, P, C', O) → poly6, l_3, p_1, c', o_1Polygon(P, L, M, E) → poly7, p_2, l_4, m_2, e_1Vector(L, C) → uVector(L, F) → vVector(L, C') → wVector(L, G) → u_1Centroid(poly4) → QCentroid(poly5) → RCentroid(poly6) → SCentroid(poly7) → TTranslate(T, w) → T'Translate(S, u) → S'Translate(R, v) → R'Translate(Q, u_1) → Q'Segment(Q, Q') → b_1Segment(R, R') → c_1Segment(S, S') → d_1Segment(T, T') → f_1Point(b_1) → UPoint(c_1) → VPoint(d_1) → WPoint(f_1) → ZVector(Q, U) → v_1Vector(R, V) → w_1Vector(S, W) → g_1Vector(T, Z) → h_1Translate(L, w_1) → L'Translate(N, w_1) → N'Translate(J, w_1) → J'Translate(O, w_1) → O'Polygon(L', N', J', O') → poly5', l', n', j', o'Translate(M, v_1) → M'Translate(L, v_1) → L'_1Translate(N, v_1) → N'_1Translate(K, v_1) → K'Polygon(M', L'_1, N'_1, K') → poly4', m', l'_1, n'_1, k'Translate(L, g_1) → L'_2Translate(P, g_1) → P'Translate(C', g_1) → C''Translate(O, g_1) → O'_1Polygon(L'_2, P', C'', O'_1) → poly6', l'_2, p', c'', o'_1Translate(P, h_1) → P'_1Translate(L, h_1) → L'_3Translate(M, h_1) → M'_1Translate(E, h_1) → E'Polygon(P'_1, L'_3, M'_1, E') → poly7', p'_1, l'_3, m'_1, e'Midpoint(H, C) → A_1Midpoint(C, G) → B_1Segment(A_1, B_1) → i_1Point(i_1) → C_1Vector(A_1, C_1) → q_1Translate(poly2, q_1) → poly2'
AI Drawing Prompt Reference
Draw an isosceles triangle to demonstrate the property of the midpoint of its base. Show that the distances from the midpoint to the two legs are equal by dragging points. Construct midpoints, mirrors, semicircles, and other geometric objects to visually prove the property. Start by plotting the intersection of axes, then create a ray and point to form the triangle. Draw a semicircle and arc, then segments from the midpoint to the legs. Build several quadrilaterals, find midpoints, draw perpendicular lines and segments, and translate centroids to show equal distances from the midpoint to the legs.
The prompt above was compiled from the original drawing commands and is for reference only.