None nowadays, because all the algebraic equations are stored in the computer programs and only the computer programs are used today. But before computers, the equations were used to calculate interest on accounts, annuities, payments, etc. The idea that there was a time when nothing happened unless a human being was commanded to make it happen is something people today find amazing. The reason you have to take algebra is because you might become one of those people who creates computer programs for the banking industry, or perhaps an engineer. Edwin