I have a few math problems that I’m unsure of how to solve. 9- 10n ,14 – 3n ,14 – 21n, (2-3n)*7, 7*2*(-3n). I have a few math problems that I’m unsure of how to solve. 9- 10n ,14 – 3n ,14 – 21n, (2-3n)*7, 7*2*(-3n).