%% 
%%  Example 03-03-9 
%%  Copyright (C) 2016 Herbert Voss
%% 
%% ==== 
% Show page(s) 1
%% 
%% 
\documentclass[]{screxa}
\pagestyle{empty}
\setlength\textwidth{134.31393pt}

%StartShownPreambleCommands

%StopShownPreambleCommands
\begin{document}
$\overline{x}+\overline{y}=\overline{z}$\\
\let\ol\overline
$ \ol{x}+\ol{A}=\ol{z} $\\[5pt]
\def\yPh{\vphantom{A}}
$ \ol{x\yPh}+\ol{A}=\ol{z\yPh} $
\end{document}
