
\begin{exercice}[Intersections de plans]
On considère un parallélépipède rectangle $ABCDEFGH$ et $I$ un point de $[AB]$. 
\begin{center}  
\begin{tikzpicture}[general,scale=0.6]
%\clip(-0.54,0.23) rectangle (9.08,7.29);
\draw[fill=H4] (1,1.5)-- (5,1)-- (5,5)--(1,5.5)--cycle;
\draw[fill=F4] (1,5.5)--(3,6.5)--(7,6)--(5,5);
\draw[fill=A4] (7,6)--(7,2)--(5,1)--(5,5);
\draw [dashed] (7,2)--(3,2.5);
\draw [dashed] (3,2.5)-- (1,1.5);
\draw [dashed] (3,2.5)-- (3,6.5);
\draw (1,5.5)--(5,5)--(7,6);
% \begin{scriptsize}
\draw(1,1.5) node[below] {$A$};
\draw(5,1) node[below] {$B$};
\draw(7,2) node[right] {$C$};
\draw(3,2.5) node[above left] {$D$};
\draw (1,5.5) node[left] {$E$};
\draw(5,5) node[above] {$F$};
\draw(7,6) node[right] {$G$};
\draw(3,6.5) node[above] {$H$};
%\draw (3,1.25) node[below] {$I$};
\draw  (3,1.25) node{$\bullet$};
% \end{scriptsize}
\end{tikzpicture}
    \end{center}
\vspace{-2em}
\begin{enumerate}
\item Reproduire la figure ci\nobreakdash-dessus et y placer le point $I$. 
\item Construire sur cette figure:
\begin{itemize}
    \item les intersections des plans $(EHI)$ et $(AFB)$;
    \item les intersections des plans  $(EHI)$ et $(HDG)$;
    \item les intersections des plans  $(EHI)$ et $(BDF)$;
    \item les intersections des plans  $(EHI)$ et $(FBC)$.
\end{itemize}
\end{enumerate}
\end{exercice}


