The phrase "in his place" is a metaphor meaning "instead of him." Alternate translation: "became king instead of Pekah" (See: [[rc://en/ta/man/translate/figs-metaphor]])
It can be stated clearly that this is the twentieth year of his reign. Alternate translation: "In year 20 of the reign of Jotham son of Uzziah" (See: [[rc://en/ta/man/translate/figs-explicit]] and [[rc://en/ta/man/translate/translate-numbers]])