Here's a breakdown:

* The Issue: Missouri applied for statehood as a slave state, which would upset the balance of power in the Senate (equal representation for free and slave states).

* The Compromise: To maintain the balance, Maine was admitted as a free state, and Missouri was admitted as a slave state.

* The Line: The compromise also established a line at 36°30′ north latitude, dividing the Louisiana Purchase into slave and free territories. This line did not apply to Missouri, but to all other areas west of the Mississippi River.

It's important to note:

* The line was not a permanent solution. It was only a temporary measure to appease both sides and avoid a major conflict.

* The compromise eventually failed. The issue of slavery continued to escalate and ultimately led to the Civil War.

Let me know if you'd like to know more about the Missouri Compromise or any other historical event!