The hardcover version of a book weighs twice as much as its paperback version. The hardcover book and the paperback together weigh 4.2 pounds. Which system of equations can be used to find h, the weight of the hardcover book, and p, the weight of the paperback?
h = p − 4.2
h = 2p
h = 4.2 − p
p = 2h
h = p − 4.2
p = 2h
h = 4.2 − p
h = 2p