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X₇₂₈¶

INTERSECTION OF LINES X₈X_9 AND X₅₇X_345

X₇₂₈ (INTERSECTION OF LINES X₈X_9 AND X₅₇X_345) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_728 = INTERSECTION OF LINES X_8X_9 AND X_57X_345."""

        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,
            construct_baseline_triangle,
            create_model,
            eval_trilinear_point,
            mittenpunkt_of,
            nagel_point_of,
            promote_point_to_top,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_00728(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_728 = INTERSECTION OF LINES X_8X_9 AND X_57X_345 on reference triangle ABC."""
            X_728 = eval_trilinear_point(model, A, B, C, '((b + c - a)**(3))', ID="X_728", classes=["selected", "target"])
            X_8 = nagel_point_of(model, A, B, C, ID="X_8", classes=["center", "incident"])
            X_9 = mittenpunkt_of(model, A, B, C, ID="X_9", classes=["center", "incident"])
            central_line(model, X_8, X_9, 8, 9, incident=True)
            X_57 = eval_trilinear_point(model, A, B, C, '1/(b + c - a)', ID="X_57", classes=["center", "incident"])
            X_345 = eval_trilinear_point(model, A, B, C, '(csc(A))/(1 - sec(A))', ID="X_345", classes=["center", "incident"])
            central_line(model, X_57, X_345, 57, 345, incident=True)
            X_200 = eval_trilinear_point(model, A, B, C, '(cot(A/2))**(2)', ID="X_200", classes=["center", "incident"])
            X_220 = eval_trilinear_point(model, A, B, C, 'a*(b + c - a)**(2)', ID="X_220", classes=["center", "incident"])
            central_line(model, X_200, X_220, 200, 220, incident=True)
            return promote_point_to_top(model, X_728)


        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_728 on the given reference triangle."""
            model = create_model('X_728 = INTERSECTION OF LINES X_8X_9 AND X_57X_345')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_00728(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-00728.json"))
            write_center_svg(
                model_acute,
                here / "x-00728.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X728¶

X₇₂₈¶