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X₃₁₀₁¶

INTERSECTION OF LINES X₂X_19 AND X₈X_20

X₃₁₀₁ (INTERSECTION OF LINES X₂X_19 AND X₈X_20) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_3101 = INTERSECTION OF LINES X_2X_19 AND X_8X_20."""

        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,
            intersect_lines,
            nagel_point_of,
            promote_point_to_top,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_03101(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_3101 = INTERSECTION OF LINES X_2X_19 AND X_8X_20 on reference triangle ABC."""
            X_2 = centroid_of(model, A, B, C, ID="X_2", classes=["center"])
            X_19 = eval_trilinear_point(model, A, B, C, 'tan(A)', ID="X_19", classes=["center"])
            X_8 = nagel_point_of(model, A, B, C, ID="X_8", classes=["center"])
            X_20 = eval_trilinear_point(model, A, B, C, 'cos(A) - cos(B)*cos(C)', ID="X_20", classes=["center"])
            central_line(model, X_2, X_19, 2, 19)
            central_line(model, X_8, X_20, 8, 20)
            X_3101 = intersect_lines(model, X_2, X_19, X_8, X_20, ID="X_3101", classes=["selected", "target"])
            X_22 = eval_trilinear_point(model, A, B, C, 'a*(b**(4) + c**(4) - a**(4))', ID="X_22", classes=["center", "incident"])
            X_55 = eval_trilinear_point(model, A, B, C, 'a*(b + c - a)', ID="X_55", classes=["center", "incident"])
            central_line(model, X_22, X_55, 22, 55, incident=True)
            return promote_point_to_top(model, X_3101)


        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_3101 on the given reference triangle."""
            model = create_model('X_3101 = INTERSECTION OF LINES X_2X_19 AND X_8X_20')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_03101(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-03101.json"))
            write_center_svg(
                model_acute,
                here / "x-03101.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X3101¶

X₃₁₀₁¶