\documentclass[a4paper,12pt]{article}
\begin{document}
\parindent=0pt

{\bf Question}

Evaluate the determinant $\left| \begin{array}{cc} 1 & 2 \\ 3 & 4
\end{array} \right|$


\vspace{.25in}

{\bf Answer}
\bigskip

$\left| \begin{array}{cc} 1 & 2 \\ 3 & 4 \end{array} \right| = 4 -
6 = -2$


\end{document}