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Decades: 740s BC 730s BC 720s BC 710s BC 700s BC - 690s BC - 680s BC 670s BC 660s BC 650s BC 640s BC
Significant People
... a being non-zero. These solutions are also called the roots of the equation. The formula reads <math> x=\frac{-b \pm \sqrt {b^2-4ac}}{2a} </math> Th ...