This is an example to illustrate my point:

Any help will be greatly appreciated.
Thanks in advance.
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Code: Select all
\documentclass{article}
\usepackage{framed}
\begin{document}
\begin{leftbar}
text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text \begin{equation}
a=b
\end{equation}
text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text text
\end{leftbar}
\end{document}
Learn LaTeX easily with newest books:
The LaTeX Beginner's Guide: 2nd edition and perfect for students writing a thesis
The LaTeX Cookbook: 2nd edition full of practical examples for mathematics, physics, chemistry, and more
LaTeX Graphics with TikZ: the first book about TikZ for perfect drawings in your LaTeX thesis