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%%  Example 02-01-5 
%%  Copyright (C) 2016 Herbert Voss
%% 
%% ==== 
% Show page(s) 1
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\documentclass[]{screxa}
\pagestyle{empty}
\setlength\textwidth{328.62788pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands
\usepackage{amsmath}
%StopShownPreambleCommands
\begin{document}
\begin{alignat}{2}
y      &= d                  &  z &= 1                  \\
y      &= cx+d & z & =x+1                               \\
y_{12} &= bx^{2}+cx+d        &  z &= x^{2}+x+1\nonumber \\
y(x)   &= ax^{3}+bx^{2}+cx+d &  z &= x^{3}+x^{2}+x+1
\end{alignat}
\end{document}
