With majestic anthems like “Killing Me Softly” and “The First Time Ever I Saw Your Face,” Ms. Flack, a former schoolteacher, became one of the most widely heard artists of the 1970s.

Roberta Flack has died at 88. The Grammy-winning singer and pianist was known for her intimate vocal and musical style on “Killing Me Softly With His Song,” “The First Time Ever I Saw Your Face” and other hits.

Roberta Flack, the R&B musician whose singing helped define the subgenre of “quiet storm” in the 1970s, is dead at 88. Flack “died peacefully surrounded by her family,” per a statement from her publicists.