% 6-3-3.tex
\documentclass{article}
\begin{document}
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\newcommand{\wrt}[1]{\makebox(0,0)[c]{#1}}
\newcommand{\lline}[1]{\line(-1,0){#1}}
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\newcommand{\uvec}[1]{\vector(0,1){#1}}
\newcommand{\dvec}[1]{\vector(0,-1){#1}}
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\newsavebox{\process}
\newsavebox{\inputoutput}
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\put(-18,-3){\framebox(36,6){}}
}
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\put(15,1){\makebox(0,0)[b]{yes}}
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\begin{center}
\begin{picture}(80,63)(0,-63)\thicklines
\put(40,0){\dvec{5}}
\put(40,-10){\usebox{\condition}}
\put(40,-10){\wrt{$\Delta\ne0$?}}
\put(20,-10){\dvec{7}}
\put(20,-20){\usebox{\process}}
\put(20,-20){\wrt{$x_{1,2}=-b/2$}}
\put(60,-10){\dvec{7}}
\put(60,-20){\usebox{\process}}
\put(60,-20){\wrt{$p=-b/2,\,q=\sqrt{\Delta}$}}
\put(60,-23){\dvec{7}}
\put(60,-33){\usebox{\process}}
\put(60,-33){\wrt{$x_1=p+q,\,x_2=p-q$}}
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\put(40,-53){\wrt{ouput $x_1,\,x_2$}}
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\end{center}
\end{document}
