[Tex/LaTex] how to justify left all numbered equations

Question

I use displayed numberd formula in lyx

the equations are appears in middel

I want to justify left the equations

I used elsarticl 2 column page format

Answer 1

Class option fleqn helps. The math indent can be configured via length \mathindent:

\documentclass[fleqn,twocolumn]{elsarticle}

\begin{document}
\noindent
Example equation:
\begin{equation}
E=mc^2
\end{equation}

\setlength{\mathindent}{0pt}

\noindent
Equation with zeroed math indent:
\begin{equation}
E=mc^2
\end{equation}
\end{document}