701 BC - King Hezekiah of Judah, backed by Egypt, revolts against king Sennacherib of Assyria. Sennacherib sacks many Palestinian cities, but fails in his attempt to take Jerusalem
... square trinomial of the form x2 + 2xy + y2. Since "2xy" in this case is (b/a)x, we must have y = b/(2a), so we add the square of b/(2a) to both sides, ...