Winners of the coin challenge

Congratulations to Julian, Luca, Daniella of the 3rd grade, Luke H. of the 6th grade, and Rania, Nina, Beckett, Ivo, Julia, and Max of the 7th grade for identifying the bag with nonstandard coins in only two weighings. They're solutions involve ignoring one bag and weighing two coins against two coins in the other bag. If the scales don't balance, you're done. If they balance, remove one coin on each side and replace those coins with the two unweighed coins in the bag. Once again if it doesn't balance you are done. If it does balance then this bag contains all standard coins and it is the other bag with nonstandard coins. by switching pairs from trial one to trial two you eliminate the possibility that the heavy and light have been together on one side in both weighings. Find Luca's illustrated solution below.