\documentclass[12pt]{article} \usepackage{amssymb,amsmath,amscd,concmath,amsfonts} \usepackage{color} \pagestyle{empty} \begin{document} \begin{equation*} G_{yr}(s)=\frac{P(CF_m+F_u)}{1+PC}=F_m+\frac{PF_u-F_m}{1+PC}, \end{equation*} \end{document}