Q:

Breaking single equation with multiple alignment

I have a set of equations that have multiple alignments, and one of these equations I want to break since it is long. The following MWE illustrates  my current solution to this problem, but it's not an elegant solution:
\documentclass{article}

\usepackage{amsmath}

\begin{document}

\begin{alignat}{2}
zero   \,\, &: \,\, 0 = + 2 -2  \\
one    \,\, &: \,\, 0 = + 2 -2 \\
            &\hphantom{\,\,:\,\, 0=}+ 2 -2
\end{alignat}

\end{document}

Is there a better solution to this than to use hphantom?

A:

\documentclass{article}
\usepackage{amsmath}

\begin{document}
\begin{alignat}{3}
  \text{zero:}\, & 0 = & \, + 2 - 2 \\
  \text{one:} \, & 0 = & \, + 2 - 2 \\
                 &     & \, + 2 - 2
\end{alignat}
\end{document}

A:

You can get by with providing a single & alignment point.

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

\begin{align}
\text{zero}:\quad 0 = &+ 2 -2 \\
\text{one}:\quad  0 = &+ 2 -2 \\
                      &+ 2 -2
\end{align}

\end{document}

