Why were the precedent set by cheif justice john marshall and the supreme court so important?

They influenced U.S. legal and economic systems.

Explanation:

John Marshall, (1755—1835), was the fourth chief justice of the United States and is regarded as the main founder of constitutional law in the United States, as well as the Supreme Court’s most influential chief justice. He was in charge of building and advocating for the establishment of constitutional law and federalism.

In Marbury v. Madison (1803), Marshall installed the Supreme Court’s right to declare unconstitutional legislation. In McCulloch v. Maryland (1819) he defended federalism by asserting that the right a state had to tax an instrument of the federal government was unconstitutional.

i think the answer is a and i hope this ; ))

the 9th amendment

explanation: