\documentclass[12pt]{article}
\usepackage{amssymb,amsmath,amscd,concmath,amsfonts}
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\begin{document}
\begin{equation*}
  \aligned 
    \dot x_v &= \begin{bmatrix} -b/m \end{bmatrix} x_v + \begin{bmatrix} 1/m & 1/m \end{bmatrix} u_v \\
    y_v &= x_v
  \endaligned
\end{equation*}
\end{document}