Meee! : < an author receives $0.60 for each hardcover book or paperback book that is sold. there were x hardcover books and 38,000 paperback books sold of her most recent book. the author received a total of $51,000 for the book sales. the equation below can be used to determine the number of hardcover books that were sold. 0.60(x + 38,000) = 51,000 how many hardcover books were sold? . a) 13,000 . b) 28,200 . c) 30,000 . d) 47,000