When an amendment is ratified by three-fourths of congress or by three-fourths of state legislatures, it becomes part of the federal constitution, and all states—even those that did not ratify the amendment—must follow the laws in the new amendment.

The question is incomplete. The question missing is the following: Is this statement true or false?

The statement is true.

Explanation:

Article V of the U.S. Constitution provides two ways in which the U.S. Constitution can be amendment: the first one enables Congress to start the process, while the second enables state legislatures to start it. In either case, if the amendment is ratified, it becomes part of the federal Constitution and all American states must abide by it.

When Congress starts the process, each house proposes an amendment with at least two-thirds of votes in favor. If the proposal reaches that majority of votes, then it has to be voted on by the state legislatures OR the state conventions. Lastly, only if the amendment is approved by at least three-fourths of the state legislatures or the state convention, it becomes a law.

When the state legislatures start the process, they propose a National Convention with two-thirds of votes. In the National Convention, the amendment can be officially proposed. If the amendment is ratified by three-fourths of the state legislatures (or conventions in three-fourths of the states), it becomes a law.

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