Final answer:
The newly independent states were joined by the Articles of Confederation before the adoption of the Constitution.
Step-by-step explanation:
Before the adoption of the Constitution, the newly independent states were joined by the Articles of Confederation. The Articles of Confederation, which were ratified in 1781, served as the first constitution of the United States. They created a weak central government and experienced many challenges, ultimately leading to their replacement by the Constitution in 1787.
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