Decades: 10s 20s 30s 40s 50s - 60s - 70s 80s 90s 100s 110s
Years: 64 65 66 67 68 - 69 - 70 71 72 73 74
Births
Deaths
... 4a2. We get <math>\left(x+\frac{b}{2a}\right)^2=\frac{-4ac+b^2}{4a^2}=\frac{b^2-4ac}{4a^2}.</math> Taking square roots of bo ...