\exercice
Voici deux exemples de zigzags :\par
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\pstGeonode[PosAngle=-87.50](2.48, 0.40){C} \pstSegmentMark{B}{C}
\pstGeonode[PosAngle=-241.00](3.63, 6.29){D} \pstSegmentMark{C}{D}
\pstGeonode[PosAngle=-90.00](9.23, 4.14){E} \pstSegmentMark{D}{E}
\pstGeonode[PosAngle=-299.50](14.83, 6.29){F} \pstSegmentMark{E}{F}
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\pstMarkAngle[MarkAngleRadius=1.5]{C}{D}{E}{}
\pstMarkAngle[MarkAngleRadius=1.5]{F}{E}{D}{}
\pstMarkAngle[MarkAngleRadius=1.5]{E}{F}{G}{}
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\hspace{2cm}
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\pstGeonode[PosAngle=-91.00,PointSymbol=x](0.20, 0.20){A}
\pstGeonode[PosAngle=-263.50](0.30, 6.20){B} \pstSegmentMark{A}{B}
\pstGeonode[PosAngle=-101.00](1.76, 0.38){C} \pstSegmentMark{B}{C}
\pstGeonode[PosAngle=-259.00](5.28, 5.23){D} \pstSegmentMark{C}{D}
\pstGeonode[PosAngle=-82.50](10.37, 2.05){E} \pstSegmentMark{D}{E}
\pstGeonode[PosAngle=-286.00](14.46, 6.44){F} \pstSegmentMark{E}{F}
\pstGeonode[PosAngle=-79.00,PointSymbol=x](15.61, 0.55){G}
\pstSegmentMark{F}{G}
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\pstMarkAngle[MarkAngleRadius=1.5]{D}{C}{B}{}
\pstMarkAngle[MarkAngleRadius=1.5]{C}{D}{E}{}
\pstMarkAngle[MarkAngleRadius=1.5]{F}{E}{D}{}
\pstMarkAngle[MarkAngleRadius=1.5]{E}{F}{G}{}
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Construire sur la figure ci-dessous les points $C$, $D$, $E$, $F$ et $G$ pour obtenir un zigzag tel que :\par
$\widehat{ABC}=67\degres \qquad \widehat{BCD}=170\degres \qquad \widehat{CDE}=178\degres \qquad \widehat{DEF}=87\degres \qquad \widehat{EFG}=52\degres \qquad $\par
Quand le travail est fait avec une bonne précision, les 
droites $(AF)$ et $(BG)$ se coupent au c\oe ur de la cible.
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