Centuries: 2nd century - 3rd century - 4th century
Decades: 230s 240s 250s 260s 270s - 280s - 290s 310s 320s 330s 340s
Years: 282 283 284 285 286 - 287 - 288 289 290 291 292
Births
Deaths
... method of completing the square[?]. <math>ax^2+bx+c=0</math> Dividing our quadratic equation by a, we have <math> x^2 + \left( \frac{b}{a} ...