Final answer:
The Missouri Compromise satisfied the people in the Missouri Territory by allowing Missouri to enter the Union as a slave state and Maine as a free state. The Southern states accepted the compromise because it protected their interests and allowed for the expansion of slavery into new territories. The Northern states accepted it because it balanced the number of free and slave states and limited the expansion of slavery.
Step-by-step explanation:
The people in the Missouri Territory were satisfied with the Missouri Compromise because it allowed Missouri to enter the Union as a slave state while also admitting Maine as a free state, maintaining the balance between free and slave states in the Senate. This compromise prevented conflict each time a territory applied for statehood by establishing a line, known as the 36°30' line, which divided the territory where slavery could expand and where it would not be allowed.
The Southern states accepted the decision because they saw it as a victory for their interests. It ensured that slaveholders in Missouri would not be deprived of their property, and it provided a framework for the expansion of slavery into new territories. The Northern states accepted the decision because it allowed Maine to enter as a free state, balancing the number of free and slave states. Additionally, it restricted the expansion of slavery into new territories.