# Creating a multiline equation [duplicate]

I am really struggling to create a multi line equation that incorporates both a matrix and a single equation that lines up the equals signs such as the one below:

So far have done the following:

\begin{equation*}
M =  U\Sigma V^{*}
\end{equation*}
$$= \textbf{U}\left[ \begin{array}{cccc} \sigma_{1} & 0 & \ldots & 0\\ 0 & \sigma_{2} & \ldots & 0\\ \vdots & \vdots & \ddots & \vdots\\ 0 & 0 & \ldots & \sigma_{m}\\ \end{array} \right]\textbf{V*}$$

• Welcome to SE! For multi row equation you should use amsmath environments as align (in your case. equations can be used only for one line equations!. – Zarko Apr 9 '16 at 14:16

You could use your code inside the align environment:

\documentclass{article}

\usepackage{amsmath}

\begin{document}

\begin{align}
\mathbf{M} &= \mathbf{U}\Sigma \mathbf{V}^{*} \nonumber\\
&= \mathbf{U}\left[\begin{array}{cccc}
\sigma_{1} & 0 & \ldots & 0\\
0 & \sigma_{2} & \ldots & 0\\
\vdots & \vdots & \ddots & \vdots\\
0 & 0 & \ldots & \sigma_{m}\\
\end{array} \right]\textbf{V*}
\end{align}

\end{document}