← etc / Encyclopedia of Triangle Centers

X₂₀₉₄¶

REFLECTION OF X₂ IN X₅₇

X₂₀₉₄ is the reflection of X₂ in X₅₇.

X₂₀₉₄ (REFLECTION OF X₂ IN X₅₇) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_2094 = REFLECTION OF X_2 IN X_57."""

        from __future__ import annotations

        from pathlib import Path

        import sympy.geometry as spg
        from geometor.model import Model

        from geometor.etc.ops import (
            central_line,
            centroid_of,
            construct_baseline_triangle,
            create_model,
            eval_trilinear_point,
            gergonne_point_of,
            intersect_lines,
            promote_point_to_top,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_02094(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_2094 = REFLECTION OF X_2 IN X_57 on reference triangle ABC."""
            X_2 = centroid_of(model, A, B, C, ID="X_2", classes=["center"])
            X_7 = gergonne_point_of(model, A, B, C, ID="X_7", classes=["center"])
            X_376 = eval_trilinear_point(model, A, B, C, '5*cos(A) - cos(B - C)', ID="X_376", classes=["center"])
            X_517 = eval_trilinear_point(model, A, B, C, '-1 + cos(B) + cos(C)', ID="X_517", classes=["center"])
            central_line(model, X_2, X_7, 2, 7)
            central_line(model, X_376, X_517, 376, 517)
            X_2094 = intersect_lines(model, X_2, X_7, X_376, X_517, ID="X_2094", classes=["selected", "target"])
            X_189 = eval_trilinear_point(model, A, B, C, 'b*c/(cos(B) + cos(C) - cos(A) - 1)', ID="X_189", classes=["center", "incident"])
            X_1121 = eval_trilinear_point(model, A, B, C, '(b*c/((b + c - a)*a - (a + b - c)*(a + c - b)))', ID="X_1121", classes=["center", "incident"])
            central_line(model, X_189, X_1121, 189, 1121, incident=True)
            return promote_point_to_top(model, X_2094)


        def build_model(
            sides: tuple[float, float, float] = (5.0, 6.0, 7.0),
            show_guides: bool = False,
        ) -> Model:
            """Build a `geometor.model.Model` for X_2094 on the given reference triangle."""
            model = create_model('X_2094 = REFLECTION OF X_2 IN X_57')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_02094(model, A, B, C)
            return model


        if __name__ == "__main__":
            here = Path(__file__).resolve().parent
            model_acute = build_model((5.0, 6.0, 7.0))
            model_acute.save(str(here / "x-02094.json"))
            write_center_svg(
                model_acute,
                here / "x-02094.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X2094¶

X₂₀₉₄¶