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X₃₂₈₉¶

INTERSECTION OF LINES X₂X_6 AND X₃X_217

Let L denote the line through X₄ perpendicular to the Brocard axis, X₃ X₆. Coefficients for a trilinear equation for L are the trilinears for X₃₂₈₉.

X₃₂₈₉ (INTERSECTION OF LINES X₂X_6 AND X₃X_217) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_3289 = INTERSECTION OF LINES X_2X_6 AND X_3X_217."""

        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,
            circumcenter_of,
            construct_baseline_triangle,
            create_model,
            eval_trilinear_point,
            promote_point_to_top,
            symmedian_point_of,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_03289(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_3289 = INTERSECTION OF LINES X_2X_6 AND X_3X_217 on reference triangle ABC."""
            X_3289 = eval_trilinear_point(model, A, B, C, '(a**(3)*(b**(2) + c**(2) - a**(2))*(b**(4) + c**(4) - a**(2)*b**(2) - a**(2)*c**(2)))', ID="X_3289", classes=["selected", "target"])
            X_2 = centroid_of(model, A, B, C, ID="X_2", classes=["center", "incident"])
            X_6 = symmedian_point_of(model, A, B, C, ID="X_6", classes=["center", "incident"])
            central_line(model, X_2, X_6, 2, 6, incident=True)
            X_3 = circumcenter_of(model, A, B, C, ID="X_3", classes=["center", "incident"])
            X_217 = eval_trilinear_point(model, A, B, C, '((sin(A))**(3))*cos(A)*cos(B - C)', ID="X_217", classes=["center", "incident"])
            central_line(model, X_3, X_217, 3, 217, incident=True)
            X_184 = eval_trilinear_point(model, A, B, C, 'a**(2)*cos(A)', ID="X_184", classes=["center", "incident"])
            X_418 = eval_trilinear_point(model, A, B, C, '(cos(A))*(csc(2*B) + csc(2*C))', ID="X_418", classes=["center", "incident"])
            central_line(model, X_184, X_418, 184, 418, incident=True)
            return promote_point_to_top(model, X_3289)


        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_3289 on the given reference triangle."""
            model = create_model('X_3289 = INTERSECTION OF LINES X_2X_6 AND X_3X_217')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_03289(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-03289.json"))
            write_center_svg(
                model_acute,
                here / "x-03289.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X3289¶

X₃₂₈₉¶