Matthew Poole and continuators on 2 Kings 3:1

NOw Jehoram the son of Ahab began to reign over Israel in Samaria, the eighteenth year of Jehoshaphat king of Judah , and reigned twelve years.

Quest. How can this be true, when Ahaziah, Iehoram's predecessor, who Reigned two Years, began his Reign in Iehoshaphat's 17th Year, 1 King. 22. 51? Ans. Either, Ahaziah Reigned the greatest part of two Years, to wit, of the 17th and 18th Years of Iehoshaphat, (parts of Years being oft called years in the computation of times, both in Scripture and other Authors) and Iehoram began his Reign towards the end of his 18th Year: or, Ahaziah Reigned part of this two Years with his Father, and the rest after him.