How to align numbers in parentheses
Here are two ways: either use a \phantom{-}
for the number without a –
(to be used for each such number), or load mathtools
and use its pmatrix*
environment, which allows for an optional alignment specifier:
\begin{equation*}
x = \begin{pmatrix*}[r]
4 \\
-3 \\
\end{pmatrix*}
\qquad
x = \begin{pmatrix}
\phantom{-} 4 \\
-3 \\
\end{pmatrix}
\end{equation*}
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\[
\left( \begin{array}{@{}r@{}}
4\\-3
\end{array}\right)
\]
\end{document}
\documentclass[12pt]{article}
\usepackage{stackengine}
\setstackEOL{\\}
\begin{document}
\[
x=\parenVectorstack[r]{4\\-3}
\]
\end{document}