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\begin{document}

%%%%%%%%%%b{gedeonInfo}%%%%%%%%%
%%--Document N° 1052680061939--
%%--Equations des hauteurs d\'un triangle--
%%%%%%%%%%e{gedeonInfo}%%%%%%%%%


\begin{exercise}
On consid\`{e}re trois points $A,$ $B$ et $C$ de coordonn\'{e}es respectives
$\left(  1;3\right)  ,$ $\left(  4;0\right)  $ et $\left(  0;-1\right)  $ dans
un rep\`{e}re orthonorm\'{e}.

\begin{enumerate}
\item D\'{e}terminer une \'{e}quation de deux hauteurs du triangle $ABC;$

\item En d\'{e}duire les coordonn\'{e}es de l'orthocentre du triangle $ABC.$
\end{enumerate}
\end{exercise}


\end{document}