%% 
%%  An UIT Edition example
%% 
%%  Example 03-02-9 on page 20.
%% 
%%  Copyright (C) 2010 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
\documentclass[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{225.70511pt}
\setlength\parindent{0pt}
\setcounter{equation}{9}
\renewcommand\theequation{3.\arabic{equation}}
\StartShownPreambleCommands

\StopShownPreambleCommands
\begin{document}
\begin{eqnarray*}
  y & = & d   \label{eq:3}\\
  y & = & cx+d            \\
  y & = & bx^{2}+cx+d     \\
  y & = & ax^{3}+bx^{2}+cx+d
\end{eqnarray*}
As Equation~\ref{eq:3} shows \ldots
\begin{eqnarray}
  y & = & x^4
\end{eqnarray}
\end{document}
