\ANG{
Aus folgenden Angaben soll ein Dreieck $ABC$ konstruiert werden:
\begin{enumerate}
\item[i)]
$a:b=5:9$
\item[ii)]
$\beta=120^0$
\item[iii)]
$h_c+h_b=9{\rm cm}$
\end{enumerate}
Fertige zun"achst eine Planfigur, konstruiere anschlie"send das 
Dreieck.
}
\LSG{
Man konstruiert z.B. $A'B'C$, und streckt im Verh"altnis
${9cm : (h_{B'}+h_{C}')}$.
Der Platzbedarf h"angt stark vom gew"ahlten L"osungsweg ab.

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}
