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X₅₅₁¶

MIDPOINT OF X₁ AND X₂

X₅₅₁ is the midpoint of X₁ and X₂.

X₅₅₁ (MIDPOINT OF X₁ AND X₂) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_551 = MIDPOINT OF X_1 AND X_2."""

        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,
            incenter_of,
            promote_point_to_top,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_00551(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_551 = MIDPOINT OF X_1 AND X_2 on reference triangle ABC."""
            X_551 = eval_trilinear_point(model, A, B, C, '(4*a + b + c)/a', ID="X_551", classes=["selected", "target"])
            X_1 = incenter_of(model, A, B, C, ID="X_1", classes=["center", "incident"])
            X_2 = centroid_of(model, A, B, C, ID="X_2", classes=["center", "incident"])
            central_line(model, X_1, X_2, 1, 2, incident=True)
            X_86 = eval_trilinear_point(model, A, B, C, 'b*c/(b + c)', ID="X_86", classes=["center", "incident"])
            X_99 = eval_trilinear_point(model, A, B, C, 'b*c/(b**(2) - c**(2))', ID="X_99", classes=["center", "incident"])
            central_line(model, X_86, X_99, 86, 99, incident=True)
            X_142 = eval_trilinear_point(model, A, B, C, 'b + c - ((b - c)**(2))/a', ID="X_142", classes=["center", "incident"])
            X_214 = eval_trilinear_point(model, A, B, C, '(b + c - 2*a)*(b**(2) + c**(2) - a**(2) - b*c)', ID="X_214", classes=["center", "incident"])
            central_line(model, X_142, X_214, 142, 214, incident=True)
            return promote_point_to_top(model, X_551)


        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_551 on the given reference triangle."""
            model = create_model('X_551 = MIDPOINT OF X_1 AND X_2')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_00551(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-00551.json"))
            write_center_svg(
                model_acute,
                here / "x-00551.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X551¶

X₅₅₁¶