Btukfyl

documentclass[border=2 mm,12pt]{standalone}

usepackage{fouriernc}

usepackage{tikz}

usepackage{tikz-3dplot}

begin{document}

    tdplotsetmaincoords{70}{180}

    begin{tikzpicture}[tdplot_main_coords,line join = round, line cap = round]

        coordinate (A) at (0,0,0);

        coordinate (S) at (7/2,{-7*sqrt(3)/6},14/3);

        coordinate (C) at (7,0,0);

        coordinate (B) at  ({65/14},{15*sqrt(3)/14},0);

        coordinate (I) at  (7/2,{-7*sqrt(3)/6},0) ;



        draw[very thick] (A) -- (B) (B) -- (C)  (S) --  (A) (S) --(B) (S) -- (C) ;



        draw[dashed ] (C) -- (A) (I) -- (A) (I) -- (B) (I) --(C) (S) --(I) ;

        draw[very thick] (I) circle ({7/sqrt(3)});

        foreach point/position in {A/below,B/below,C/below,

            I/below,S/above}

        {

            fill (point) circle (1.5pt);

            node[position=3pt] at (point) {$point$};

        }

          end{tikzpicture}

  end{document}

documentclass[border=2 mm,12pt]{standalone}

usepackage{fouriernc}

usepackage{tikz}

usepackage{tikz-3dplot}

begin{document}

    tdplotsetmaincoords{70}{180}

    begin{tikzpicture}[tdplot_main_coords,line join = round, line cap = round]

        coordinate (A) at (0,0,0);

        coordinate (S) at (7/2,{-7*sqrt(3)/6},14/3);

        coordinate (C) at (7,0,0);

        coordinate (B) at  ({65/14},{15*sqrt(3)/14},0);

        coordinate (I) at  (7/2,{-7*sqrt(3)/6},0) ;



        draw[very thick] (A) -- (B) (B) -- (C)  (S) --  (A) (S) --(B) (S) -- (C) ;



        draw[dashed ] (C) -- (A) (I) -- (A) (I) -- (B) (I) --(C) (S) --(I) ;

        draw[very thick] (I) circle ({7/sqrt(3)});

        foreach point/position in {A/below,B/below,C/below,

            I/below,S/above}

        {

            fill (point) circle (1.5pt);

            node[position=3pt] at (point) {$point$};

        }

          end{tikzpicture}

  end{document}

documentclass[border=2 mm,12pt]{standalone}

usepackage{fouriernc}

usepackage{tikz}

usepackage{tikz-3dplot}

begin{document}

    tdplotsetmaincoords{70}{180}

    begin{tikzpicture}[tdplot_main_coords,line join = round, line cap = round]

        coordinate (A) at (0,0,0);

        coordinate (S) at (7/2,{-7*sqrt(3)/6},14/3);

        coordinate (C) at (7,0,0);

        coordinate (B) at  ({65/14},{15*sqrt(3)/14},0);

        coordinate (I) at  (7/2,{-7*sqrt(3)/6},0) ;



        draw[very thick] (A) -- (B) (B) -- (C)  (S) --  (A) (S) --(B) (S) -- (C) ;



        draw[dashed ] (C) -- (A) (I) -- (A) (I) -- (B) (I) --(C) (S) --(I) ;

        draw[very thick] (I) circle ({7/sqrt(3)});

        foreach point/position in {A/below,B/below,C/below,

            I/below,S/above}

        {

            fill (point) circle (1.5pt);

            node[position=3pt] at (point) {$point$};

        }

          end{tikzpicture}

  end{document}

documentclass[border=2 mm,12pt]{standalone}

usepackage{fouriernc}

usepackage{tikz}

usepackage{tikz-3dplot}

begin{document}

    tdplotsetmaincoords{70}{180}

    begin{tikzpicture}[tdplot_main_coords,line join = round, line cap = round]

        coordinate (A) at (0,0,0);

        coordinate (S) at (7/2,{-7*sqrt(3)/6},14/3);

        coordinate (C) at (7,0,0);

        coordinate (B) at  ({65/14},{15*sqrt(3)/14},0);

        coordinate (I) at  (7/2,{-7*sqrt(3)/6},0) ;



        draw[very thick] (A) -- (B) (B) -- (C)  (S) --  (A) (S) --(B) (S) -- (C) ;



        draw[dashed ] (C) -- (A) (I) -- (A) (I) -- (B) (I) --(C) (S) --(I) ;

        draw[very thick] (I) circle ({7/sqrt(3)});

        foreach point/position in {A/below,B/below,C/below,

            I/below,S/above}

        {

            fill (point) circle (1.5pt);

            node[position=3pt] at (point) {$point$};

        }

          end{tikzpicture}

  end{document}

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