Decades: 1600s BC 1590s BC 1580s BC 1570s BC 1560s BC - 1550s BC - 1540s BC 1530s BC 1520s BC 1510s BC 1500s BC
Significant People
... it discriminates between three qualitatively different cases: If the discriminant is zero, then there is a repeated solution x, and this solution is real. ...