Decades: 740s 750s 760s 770s 780s - 790s - 800s 810s 820s 830s 840s
Years: 791 792 793 794 795 - 796 - 797 798 799 800 801
Births
Deaths
... must have y = b/(2a), so we add the square of b/(2a) to both sides, ...