December 22 - NBC begins broadcasting from the Empire State Building transmitter
December 23 - Don Lee Broadcasting[?] signs on W6XAO (later KTSL) from Los Angeles with electronic television. Don Lee should be considered as the world's first electronic television service.
... from both sides, we get
<math>x=\frac{-b}{2a}\pm\frac{\sqrt{b^2-4ac}}{2a}=\frac{-b\pm\sqrt{b^2-4ac}}{2a}.</math>
Generalizations
The formula and ...