1914 - Copyright: In New York City the ASCAP (for American Society of Composers, Authors and Publishers) is established to protect the copyrighted musical compositions of its members.
1991 - Gulf War: Two laser-guided "smart bombs" destroy an underground bunker in Baghdad killing hundreds of Iraqis. Iraqi officials claim that the bunker was a bomb shelter but United States military intelligence identified it as a military facility.
... the common denominator is 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 both ...