March 13 - In the US, Bryan Adams "Heat of the Night" becomes the first single to be commercially released on cassette. Cassette singles become known as cassingles[?].
April 23 - Carole King sues the owner of her record company, Lou Adler, claiming that she is owed more than $400,000 in royalties. King also asks for rights to her old recordings.
... we add the square of b/(2a) to both sides, getting
<math>x^2+\frac{b}{a}x+\frac{b^2}{4a^2}=-\frac{c}{a}+\frac{b^2}{4a^2}.</math>
The left side is now a ...