How can I portray my lm() model across different ggplot scatterplot differently?

I am currently regressing GDP on multiple factors (7 different variables to be exact), My x variable is quarterly Dates (2006-Q1 to 2020-Q4). I need need to plot my scatter plot for the GDP with Date and plot my lm() linear line on top of it. I can not use geom_smooth() as it wont inclu开发者_开发知识库de all the regression coefficients and i can't do it any other way and am stuck. I attempted to use predict but when plotted its a non linear line. To sum it up, I need to take my lm() model and put it on my scatterplot.