Prevent Line Break Before flalign* Block in Itemize Environment

Question

My question is similar to Prevent line break before equation environment in enumerated list item, but I want to use an unnumbered left align block. (Like the poster of the linked question, I would like to avoid using the IEEEtran document class.)

\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{itemize}
    \item[(a)]
        \begin{flalign*}
            x &= y &\\
              &= z
        \end{flalign*}
\end{itemize}
\end{document}

I want the equation to begin right after the (a) label. Thank you!

Answer 1

You could use a top-aligned aligned (pun intended) environment:

Observe that aligned, unlike flalign*, does not initiate and terminate math mode by itself; instead,aligned must be embedded in a math-mode group (here: the group that begins and ends with $ symbols).

\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{itemize}
    \item[(a)]
        \begin{flalign*}
            x &= y &\\
              &= z
        \end{flalign*}
    \item[(b)]
        $\begin{aligned}[t]
            x &= y \\
              &= z
        \end{aligned}$
\end{itemize}
\end{document}