\input{Dias.tikz}

\begin{tikzpicture}
\pgfmathparse{3.5} \let\x\pgfmathresult;
\pgfmathparse{2} \let\y\pgfmathresult;
\pgfmathparse{1} \let\yy\pgfmathresult;

      \node[mybox,text width=5cm] (GN)
      at (0,0)
      {
         Geometria Neutra\\
         (axiomas da geometria neutra)
      };
      
      \node[mybox,text width=6.25cm] (GE)
      at (-\x,-\y)
      {
         Geometria Euclidiana\\
         (axioma de paralelismo de Euclides)
      };
      
      
      \node[mybox,text width=6.25cm] (GH)
      at (\x,-\y)
      {
         Geometria Hiperb\'olica\\
         (axioma de paralelismo de Lobachevsky)
      };
      
      \coordinate (C) at  ( 0,-\yy);
      \coordinate (PL) at (-\x,-\yy);
      \coordinate (PR) at ( \x,-\yy);
      
      \draw[] (GN.south) -- (C);
      \draw[] (PL) -- (C);
      \draw[] (PR) -- (C);
      \draw[] (PL) -- (GE.north);
      \draw[] (PR) -- (GH.north);
\end{tikzpicture}
