# Aligning at the equal sign while keeping whole block aligned to the left

In my TeX document, I have my equations all pushed to the left instead of appearing in the center and I have it set so the output is a single "sheet" cropped to the output. The code for it is this:

\documentclass[varwidth=true, border=10pt]{standalone}
…
\begin{document}

\begin{flushleft}
% Equations go here.
\end{flushleft}

\end{document}


I want to get an equation to look like this:

f(x) = k * (x + c) + z
= k * x + k * c + z


I'd like the lines that come after the first one to be aligned to the equal sign in the first and I want to keep it all in $…$. I can do that in OpenOffice using %phantom{}, but I don't know how to do that with LaTeX.

• Are you looking for the fleqn option? – user121799 Mar 22 '18 at 18:43
• @marmot I have no idea what that is. – Melab Mar 22 '18 at 18:46
• \documentclass[fleqn, ...]{article}. – GuM Mar 22 '18 at 18:47
• May I ask why you insist on placing the formulae inside $...$? – GuM Mar 22 '18 at 18:58
• @GuM I want to keep it inbetween a pair of dollar signs because that makes it easy to distinguish math formatting from non-math formatting in the source code. – Melab Mar 22 '18 at 19:07

This is too long for a comment. Just add the fleqn option to your document.

\documentclass[fleqn]{article}
\usepackage{amsmath}
\begin{document}
Bla bla bla
\begin{align}
f(x) &= k * (x + c) + z \notag\\
&= k * x + k * c + z
\end{align}
bla bla bla
\end{document}


• I want to keep it in a $…$. – Melab Mar 22 '18 at 18:50
• @Melab what is "it" and did you notice that align is a math environment, which, as the name suggests, aligns lines of equations? (That is, everything inside an align environment is in math mode.) – user121799 Mar 22 '18 at 18:52
• "It" refers to the whole equation and I want to keep it inbetween a pair of dollar signs because that makes it easy to distinguish math formatting from non-math formatting in the source code. – Melab Mar 22 '18 at 19:06
• @Melab But there is no need for that. Putting something between  signs just means you put the stuff in math mode. The align environment also does that. – user121799 Mar 22 '18 at 19:09 • @marmot -- i think this would more suitably be handled with equation and split since it has only one equation number. and really, the op needs to read some basic amsmath documentation. – barbara beeton Mar 22 '18 at 19:34 You can still use \phantom inside math mode: \documentclass{article} \setlength{\parindent}{0pt}% Remove paragraph indentation \begin{document} \begin{flushleft}f(x) = k \times (x + c) + z\phantom{f(x) =} = k \times x + k \times c + z$\end{flushleft}$
\begin{array}{ @{} r @{} l @{} }
f(x) = {} & k \times (x + c) + z \\
& = k \times x + k \times c + z
\end{array}
\$

\end{document}


Alternatively, alignment is also possible if you place content inside an array (second option provided above).

• Can I use \phantom{} inside the same pair of dollar signs after a double backslash? – Melab Mar 22 '18 at 19:10
• @Melab: Inside array? Yup. – Werner Mar 22 '18 at 19:14