Final answer:
Young people used the First Amendment freedom of speech, the Fourteenth Amendment equal protection clause, and the Nineteenth Amendment as constitutional rights to get the voting age lowered.
Step-by-step explanation:
The young people used several constitutional rights to advocate for lowering the voting age. One key right was the First Amendment's freedom of speech, which allowed them to express their opinions and rally support for their cause. They also relied on the Fourteenth Amendment's equal protection clause, arguing that denying them the right to vote based on age was unconstitutional discrimination. Finally, they used the Nineteenth Amendment, which granted women the right to vote, as a precedent for expanding voting rights to other groups.
Learn more about Constitutional rights for lowering voting age