Final answer:
Aaron Burr, who was the vice president under Thomas Jefferson, killed Alexander Hamilton in a duel on July 11, 1804, leading to the end of Hamilton's life and Burr's political career.
Step-by-step explanation:
The US vice-president who killed Alexander Hamilton in a duel was Aaron Burr. Despite the fact that duelling was illegal in both New York and New Jersey, the duel took place following formal duelling protocols. On July 11, 1804, in Weehawken, New Jersey, Alexander Hamilton was mortally wounded by Aaron Burr.
Hamilton, a notable figure in the founding of the United States, had held the position of the nation's first Secretary of the Treasury and was the founder of the Federalist Party. The duel was a culmination of a long-standing feud between Burr and Hamilton, which began more than a decade earlier and was fueled by their deep political and personal differences. Burr, who was serving as Jefferson's first vice president at the time, saw his political career disintegrate following the duel, becoming most notorious for his fatal confrontation with Hamilton.