# Multiple equations in square bracket matrix [duplicate]

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When solving many equations you usually stuff them in matrices and solve them using Gauss-Jordan elimination. Where I come from, we write it like this and this is what should appear in my document: The gray parts of image are there for clarity and are not part of what I need. I just need (n+1) x n matrix with separation line. I will also need to display multiple of the matrices next to each other to show the GEM process: How can I do it?

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• That's really interesting, thanks. I'll try to figure out how to make the brackers square. – Tomáš Zato Apr 25 '15 at 16:39
• If you want to use gauss, there's a way for using square brackets. Just do \begin{gmatrix}[b] instead of \begin{gmatrix}[p] – egreg Apr 25 '15 at 16:45
• The documentation for the gauss package on page 8 explains how to change the delimiters texdoc.net/texmf-dist/doc/latex/gauss/gauss-doc.pdf – R. Schumacher Apr 25 '15 at 16:46

## 1 Answer

Taken from Stefan's answer in https://tex.stackexchange.com/a/2244/46716

\documentclass{article}
\usepackage{amsmath}

\makeatletter
\renewcommand*\env@matrix[*\c@MaxMatrixCols c]{%
\hskip -\arraycolsep
\let\@ifnextchar\new@ifnextchar
\array{#1}}
\makeatother

\begin{document}

$\begin{bmatrix}[*3c|c] 2 & 5 & 0 & 7 \\ 3 & 0 & 4 & 2 \\ 4 & 2 & 6 & 3 \\ \end{bmatrix} \Rightarrow \begin{bmatrix}[*3c|c] 2 & 2 & 2 & 6 \\ 3 & 0 & 4 & 6 \\ 5 & 2 & 6 & 6 \\ \end{bmatrix}$

\end{document} 