Answer:
The 3rd estate upset about the Estates-General because they not treated as fair as the other two estates.
Explanation:
In an attempt to address the economic crisis, Louis XVI of France called the Estates-General, represented the three estates including the nobles, the clergy, and the commons.
The voting procedure in the Estates-General required each estate to vote as a body, where the members of the Third Estate did not support it. The reason for disagreement happened because they found themselves defeated by the other two estates. They wanted the vote to be based on the number of members.
On June 20, 1789, the commons in the Estates-General found themselves out of their assemblage place and saw it as a plot by the King to break them. The members relocated their meeting at a tennis court declared themselves as National Assembly and signed an affirmation to maintain attending until the new constitution for France written. The Tennis Court Oath was a promise that showed power came from people and not from the monarchy.