“Yeah” is an informal spoken form of “yes”. Notice that the short /e/ becomes the longer sound /eə/, or, for a lot of us, it sounds more like /e:/. There’s a lot of stress and quite big intonation on “right”.
Actually, when we say this, we usually mean the opposite. It usually means “I think that’s nonsense.” It’s very informal. It’s definitely not the right thing to say in reply to Tuesday’s phrase!