how to set the \quad space between the equation and equation number with centered

How to set the \quad space between the equation and equation number with centered output i.e equation will be centered the output should be like below

A + b (1)

A + b (2)

• Welcome to TeX.sx! Please add a minimal working example (MWE) that illustrates your problem. It will be much easier for us to reproduce your situation and find out what the issue is when we see compilable code, starting with \documentclass{...} and ending with \end{document}. – Marco Daniel Apr 6 '13 at 11:56
• What is qud? Did you try align? – Marco Daniel Apr 6 '13 at 11:57
• Welcome to TeX.sx! What you want to achieve is unclear. Please reformulate your question. – jub0bs Apr 6 '13 at 12:11
• @MarcoDaniel - the OP may have meant to write \quad. Just a guess. – Mico Apr 6 '13 at 12:11
• I think the OP wants centred equations with equation numbers on the right, albeit not to the far right... – jub0bs Apr 6 '13 at 12:20

\documentclass{article}
\usepackage{amsmath}
\begin{document}

The usual setting (in \LaTeX\ and generally) is to have the numbers flush to the edge
\begin{align}
A &+ b \\
Ax &+ zz
\end{align}

But if you really need this layout you can do the following
(replacing 1em by whatever space you need):

\newcommand\mytag{\hspace*{1em}\refstepcounter{equation}(\theequation)}
\begin{aligned} A &+ b &\mytag\\ Ax &+ zz &\mytag \end{aligned}

\end{document}