# Equation sub-numbering [duplicate]

How can I label my equations as:

a = b+c (1(a))
d = f+g (1(b))


Please advice as I have used simple labeling structure \label but don't know how to handle the letters.

You can use the subequations environment from amsmath:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\begin{subequations}
\begin{align}
y & = d \\
y & = cx + d \\
y & = bx ^{2}+ cx + d \\
y & = ax ^{3}+ bx ^{2}+ cx + d
\end{align}
\end{subequations}

\end{document}


• Thanks Gonzalo for your prompt reply. What if I can't write my subequation under one \begin {subequation} and \end{subequation}? Actually my two equations have text in between, mean 1(a) then some text then 1(b). I hope i am making clear here. Thanks for your help. – user47254 Mar 4 '14 at 2:46
• @user47254 For short texts you can use \intertext{text text...}. – Gonzalo Medina Mar 4 '14 at 3:17