Decades: 730s 740s 750s 760s 770s - 780s - 790s 800s 810s 820s 830s
Years: 780 781 782 783 784 - 785 - 786 787 788 789 790
Births
Deaths
... sides, getting <math>x^2+\frac{b}{a}x+\frac{b^2}{4a^2}=-\frac{c}{a}+\frac{b^2}{4a^2}.</math> The left side is now a perfect square; it is the square of ...