\begin{exercice}
Même énoncé que l'exercice \RefExercice{2G4_E_lireequationdedroite}.
\begin{center}
\begin{tikzpicture}[general, scale=0.85]
\draw [quadrillageNIV2, step=0.5](-4,-3) grid (5,3);
\draw [quadrillage](-4,-3) grid (5,3);
\axeX{-4}{5}{0.5}
\axeY{-3}{3}{0.5}
\origine
\draw [epais,color=J1] (-4,1)--(5,1);
\draw [epais,color=F1] (-1,3)--(2,-3);
\draw [epais,color=G1] (0.333,3)--(-1.667,-3);
\draw [epais,color=A1](-2,-3)--(2,3);
 \draw [epais,color=C1](-4,0.333)--(5,-2.667);
\draw[color=J1] (2.61,1.4) node {{\boldmath ${\cal D}_1$}};
\draw[color=F1] (-1.3,2.6) node {{\boldmath ${\cal D}_3$}};
\draw[color=G1] (-0.5,2.69) node {{\boldmath ${\cal D}_4$}};
\draw[color=A1] (0.88,2.69) node {{\boldmath ${\cal D}_5$}};
\draw[color=C1] (3.67,-2.45) node {{\boldmath ${\cal D}_6$}};
\end{tikzpicture}
 \end{center}

\end{exercice}
