Hello,
Sorry if the example is not minimal but otherwise it would be difficult to
explain the problem. The text overflows on the figure and I do not know how
to correct this.
Thank you
Fabrice


\usemodule[pgfplots]

\pgfplotsset{compat=newest}

\starttext
\placefigure[right,none]{}{
\hbox{\framed{\switchtobodyfont[8pt]
\starttikzpicture[/pgf/declare function={g(\x)=3*\x +7;},/pgf/declare
function={f(\x)=-4*\x +1;},/pgf/declare function={h(\x)=2*\x
-5;}]
\startaxis[
 restrict x to domain=-20:20, xmax=20, xmin=-20,
 restrict y to domain=-25:30, ymax=30, ymin=-25,
 x=0.1cm,
 y=0.1cm,
 axis x line = middle,
 axis y line = middle,
 axis line style =  thick,
 major grid style=gray,
 minor grid style=gray,
 tickwidth=0.1cm,
 xtick align=outside,
 ytick align=outside,
 grid=both,
 xtick={-15,-10,...,15},
 ytick={-20,-15,...,25},
 xticklabels={\empty,\empty,\empty,\empty,5,\empty,\empty,\empty},
 yticklabels={\empty,\empty,\empty,\empty,\empty,5,\empty,\empty,\empty,\empty,\empty,\empty},
 extra x ticks={-20,20},
 extra x tick label={\null},
 extra y ticks={-25,30},
 extra y tick label={\null},
 extra tick style={tick style={draw=none}},
 every tick/.style={
        black,
        thick,
      },
 y tick label style={
           /pgf/number format/1000 sep={}
       },
 xlabel=$x$,ylabel=$y$,
 every axis x label/.style={
    at={(ticklabel* cs:1.01)},
    anchor=west,
},
every axis y label/.style={
    at={(ticklabel* cs:1.01)},
    anchor=south,
},
 samples=2000,
 >=stealth,
]

\addplot [smooth,domain=-20:20,thick,darkblue] {f(x)} ;
\addplot [smooth,domain=-20:20,thick,darkred] {g(x)} ;
\addplot [smooth,domain=-20:20,thick,yellow] {h(x)} ;

\draw[thick,darkgreen](5,-25)--(5,30) ;

\node[below left=2pt] at (-0.1,-0.1,0) {\math{0}} ;

\stopaxis
\stoptikzpicture}}}
  \startitemize[n]
  \item On considère les droites \math{{\cal D}\,\colon x=5} et \math{{\cal
D'}\,\colon y=3x+7}.

    \startitemize[a]
    \item Que vaut l'abscisse du point d'intersection de \math{{\cal D}} et
\math{{\cal D'}} ?
    \item Calculer alors son ordonnée.
    \item Interpréter graphiquement le résultat sur le graphique.
    \stopitemize
  \item On considère les droites \math{\Delta \,\colon y=-4x+1} et
\math{\Delta '\,\colon y=2x-5}.

    \startitemize[a]
    \item Résoudre l'équation \math{-4x+1=2x-5}.
    \item Donner une interprétation graphique de la solution obtenue.
    \item Donner les coordonnées du point d'intersection de \math{\Delta}
et \math{\Delta '}.
    \item Interpréter graphiquement le résultat sur le graphique.
    \stopitemize
  \stopitemize
\stoptext