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X₆₃₁¶

3/5*OG

X₆₃₁ = reflection of X₆₃₂ in X₁₄₀

X₆₃₁ (3/5*OG) constructed on acute reference triangle \((a, b, c) = (5, 6, 7)\) with unit baseline AB = \(1\).¶

"""GEOMETOR construction model for X_631 = 3/5*OG."""

        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,
        )
        from geometor.etc.render import write_center_svg


        def construct_x_00631(
            model: Model, A: spg.Point, B: spg.Point, C: spg.Point
        ) -> spg.Point:
            """Construct X_631 = 3/5*OG on reference triangle ABC."""
            X_631 = eval_trilinear_point(model, A, B, C, '2*cos(A) + cos(B)*cos(C)', ID="X_631", classes=["selected", "target"])
            X_2 = centroid_of(model, A, B, C, ID="X_2", classes=["center"])
            X_3 = circumcenter_of(model, A, B, C, ID="X_3", classes=["center"])
            central_line(model, X_2, X_3, 2, 3)
            X_54 = eval_trilinear_point(model, A, B, C, 'sec(B - C)', ID="X_54", classes=["center", "incident"])
            X_69 = eval_trilinear_point(model, A, B, C, '(cos(A))/a**(2)', ID="X_69", classes=["center", "incident"])
            central_line(model, X_54, X_69, 54, 69, incident=True)
            X_36 = eval_trilinear_point(model, A, B, C, '1 - 2*cos(A)', ID="X_36", classes=["center", "incident"])
            X_388 = eval_trilinear_point(model, A, B, C, 'b*c*(a**(2) + (b + c)**(2))/(b + c - a)', ID="X_388", classes=["center", "incident"])
            central_line(model, X_36, X_388, 36, 388, incident=True)
            return promote_point_to_top(model, X_631)


        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_631 on the given reference triangle."""
            model = create_model('X_631 = 3/5*OG')
            A, B, C = construct_baseline_triangle(model, *sides, show_guides=show_guides)
            construct_x_00631(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-00631.json"))
            write_center_svg(
                model_acute,
                here / "x-00631.svg",
                subtitle="(a, b, c) = (5, 6, 7) | AB = 1",
            )
        

X631¶

X₆₃₁¶