# How to align multiple symbols for a long equation?

\documentclass[11pt]{article}
\usepackage{xfrac, array, tabu, multirow, graphicx, setspace, dcolumn, tikz}
\usepackage[fleqn]{mathtools}
%the argument for d specifies the maximum number of decimal places
\usepackage[ngerman]{babel}
\usepackage[applemac]{inputenc}
\begin{document}
\begin{align}
\bar{x}&=7+(2\times9) + (2\times10) + (4\times11) + (6\times12) + (7\times14)\\
&+(2\times15) + (3\times16) + 17 + 18 + 19\\
\bar{x}&=14
\end{align}
\end{document}


I was looking long and hard for an answer, I believe {alignat*} is capable to do what I want, I just can't figure out how. I want the too long equation to align as follows: 1st and 3rd row the = should be aligned. But I also want the 1st and 2nd row to be aligned where the first + comes in.

You can use an aligned as follows:

\documentclass[11pt]{article}

\usepackage[fleqn]{mathtools}
\begin{document}

\begin{align}
\bar{x}&=\!
\begin{aligned}[t]
7&+(2\times9) + (2\times10) + (4\times11) + (6\times12) + (7\times14)\\
&+(2\times15) + (3\times16) + 17 + 18 + 19\\
\end{aligned}\\
\bar{x}&=14
\end{align}

\end{document}


The \hphantom command is what you are looking for:

\documentclass{article}

\usepackage{amsmath}

\begin{document}

\noindent Either
\begin{align}
\bar{x} &= 7 + (2\times9) + (2\times10) + (4\times11) + (6\times12) + (7\times14)\notag\\
&\hphantom{{}= 7} + (2\times15) + (3\times16) + 17 + 18 + 19\\
\bar{x} &= 14
\end{align}
or
\begin{align}
\begin{split}
\bar{x} &= 7 + (2\times9) + (2\times10) + (4\times11) + (6\times12) + (7\times14)\\
&\hphantom{{}= 7} + (2\times15) + (3\times16) + 17 + 18 + 19
\end{split}\\
\bar{x} &= 14
\end{align}
is probably what you are looking for.

\end{document}


P.S. Remember {} before = to get the correct horizontal spacing.

• \hphantom is in the TeX core AFAIR, it has nothiong to do with mathtools. – daleif Aug 2 '13 at 13:54
• I see; I'll change my comment accordingly. – Svend Tveskæg Aug 2 '13 at 13:54
• Perhaps the first two lines could be wrapped inside a split environment, so the first expression receives just one number instead of the current two numbers (which are odd). – Gonzalo Medina Aug 2 '13 at 14:16
• @GonzaloMedina Yes.... or just use a \notag at the end of the first line. – Svend Tveskæg Aug 2 '13 at 21:47
• @SvendTveskæg there's a difference, though: using split the number will be vertically centered between the two lines. – Gonzalo Medina Aug 2 '13 at 21:51