% background color
% - rendered as text
% - use `$...$` to switch back to math mode
\colorbox{orange}{$F=ma$ ... (1)}
F=ma ... (1)
% border and background color
% - rendered as text
% - use `$...$` to switch back to math mode
\fcolorbox{orange}{red}{$F=ma$ ... (1)}
% {border}{background}{...}