15 added to the quotient of 8 and a number is 7. Take this algebraic expression in pieces: The phrase a number means an arbitrary variable. Let's call it x. The quotient of 8 and a number: 8/x 15 added to this quotient: 8/x + 15 The word is means an equation, so we set 8/x + 15 equal to 7 8/x + 15 = 7