# Adding a bracket to a set of equations [duplicate]

So I'm a first time Latex learner and I'm still learning the roots, but I want to do something similar to the example given in the picture.

• Which aspects of this screenshot are you trying to reproduce? The curly brace down the left-hand side, the colons, the alignment of the three equations, how to to place material in a subscript position, or something else? Please be specific. – Mico Sep 17 '16 at 22:39
• – Au101 Sep 17 '16 at 22:52
• @Au101 - As of now, it's not clear which part, or parts, of the screenshot the OP is looking to reproduce. The curly brace is only of several possible style elements... Let's see if the OP responds to my inquiry. If we don't get an answer, the posting can be closed as "unclear what you're asking". – Mico Sep 17 '16 at 22:55
• @Mico You make a fair point, but the title does say "adding a bracket to a set of equations" ... D. Brito you'd definitely benefit from having a quick read through the links in any case :) – Au101 Sep 17 '16 at 22:57
• Ok, so I'm trying to add the curly brace down the left together with the equations. I'm sorry for not being clear. – D. Brito Sep 17 '16 at 23:00

\documentclass{article}

\usepackage{amsmath}

\begin{document}
\left\{ \begin{aligned} y & = x\\ z & = a. \end{aligned} \right.
\end{document}


* EDIT *

As Werner commented, you can alternatively use the cases or dcases environments; the latter needs the mathtools package. The cases environment is really intended for the end of a line with something else in front.

\documentclass{article}

\usepackage{mathtools}

\begin{document}
\left\{ \begin{aligned} y & = x\\ z & = a. \end{aligned} \right.
$$\begin{dcases} y = x\\ z = a. \end{dcases}$$

\end{document}

• cases or dcases seem appropriate here... – Werner Sep 17 '16 at 23:36
• I don't think cases is right unless there's something to the left of the \{, like f(x)=... dcases works, but I've often had the need for the somewhat more flexible and general construct I used in the original example. – JPi Sep 17 '16 at 23:45