\input{Dias.tikz}

\begin{tikzpicture}[]
   \pgfmathparse{4.5} \let\x\pgfmathresult
   \pgfmathparse{2.25} \let\xeq\pgfmathresult

   \node at (-\x,0) [mybox,text width=3.5cm]
   {Geometria Euclidiana};
   
   \node at (0,0) [mybox,text width=3.5cm]
   {
      Geometria Neutra +\\ APE
   };
   
   \node at (\x,0) [mybox,text width=3.5cm]
   {
      Geometria Neutra +\\ Substituto para o APE
   };
   \node[] at (-\xeq,0) {\Large{$=$}};
   \node[] at ( \xeq,0) {\Large{$=$}};
\end{tikzpicture}