\documentclass[letterpaper]{article}
\usepackage{amsmath,unicode-math,geometry}
\setmainfont{Latin Modern Roman}
\setmathfont{Asana Math}
%\usepackage{xcolor}
\usepackage{graphicx}

\begin{document}

First, an inline
\includegraphics[scale=1.0]{/usr/local/apache2/icons/pdf.png}
image.

And some other images...

\includegraphics[scale=0.25]{/usr/local/apache2/icons/pdf.png}

\includegraphics[scale=4.00]{/usr/local/apache2/icons/pdf.png}

And done.

\end{document}

