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I want to align equations inside an enumeration, so I use the aligned environment and its [t] option to make the first equation appear on the same baseline as the item label:

\usepackage{amsmath, enumitem}

\begin{enumerate}[align=left, leftmargin=*, label=\large\sffamily\bfseries \alph*)]
  \item $a = 1$
    a &= 1\\
    b &= 2\\
    c &= 3

This works quite well, but I noticed that the aligned environment introduces a small indentation (I added the red line for better visualization):

aligned indentation

How can this be solved? Or is there an even better alternative to aligned?

marked as duplicate by egreg, Peter Jansson, Ludovic C., karlkoeller, Red Nov 14 '13 at 15:51

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