Sabrina Carpenter, Loretta Lynn and SZA sing about all the points on a love triangle. By Lindsay Zoladz Today’s playlist is all about one of popular music’s favorite shapes: the love triangle.

The secret of Loretta Lynn, historians Mary Bufwack and Robert Oermann write, “is in her honesty. Her strength is in her womanhood. Her pride is in her working-class background.” She achieved ...