%% 
%%  Example 01-04-2 
%%  Copyright (C) 2017 Herbert Voss
%% 
%% ==== 
% Show page(s) 1
%% 
%% 
\documentclass[]{screxa}
\pagestyle{empty}
\setlength\textwidth{304.62788pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands

%StopShownPreambleCommands
\begin{document}
\begin{equation}
x=\left\{ \begin{array}{cl}
0 & \textrm{if }A=\ldots\\
1 & \textrm{if }B=\ldots\\
x & \textrm{this runs with as much text as you like, but without an
	 ragged right text.}\end{array}\right.
\end{equation}
\end{document}
