Answer:
In 1819, Missouri applied to become a slave state, but this would upset the balance of the equal number of slave states and free states (11 and 11). The slave states would have a larger representation in the Senate, so they needed a compromise. "To keep the peace, Congress did a two-part compromise, granting Missouri's request but also admitting Maine as a free state. It also passed an amendment that drew an imaginary line across the former Louisiana Territory, making a boundary between free and slave regions that remained the law of the land until it negated by the Kansas-Nebraska Act of 1854."
Step-by-step explanation: