side-by-side equations, with equation numbers for each

Question

The align command from amsmath allows me to put two equations side-by-side:

\begin{align}
x = y && a = b
\end{align}

Unfortunately for my purposes, this shows both equations under one equation number:

x = y    a = b   (1)

Is there any way to give them individual numbers, so that the output looks like this?:

x = y (1)    a = b (2)

Answer 1

You can use minipages to wrap the equations:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\noindent\begin{minipage}{.5\linewidth}
\begin{equation}
  a = b + c.
\end{equation}
\end{minipage}%
\begin{minipage}{.5\linewidth}
\begin{equation}
  d = e + f.
\end{equation}
\end{minipage}

\end{document}

Answer 2

\usepackage{multicol}
...
\begin{multicols}{2}
  \begin{equation}
    a=b
  \end{equation}\break
  \begin{equation}
    b=c
  \end{equation}
\end{multicols}

Answer 3

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

\noindent
\begin{tabularx}{\linewidth}{@{}XX@{}}
\begin{equation}
  a = b + c.
\end{equation}
&
\begin{equation}
  d = e + f.
\end{equation}
\end{tabularx}

\end{document}