Murray, who fights for the Moss Side amateur club and is a former room-mate of Amir Khan, added: "It's not bad going to have two Lancashire fighters reaching two Olympics in a row."
Showing impressive maturity, Murray raced into a 5-0 lead and, despite his lead being pegged back to two points at one stage, the British boxer never had to chase the fight.
Edwards said: "Joe has got the first one on the board and it is a remarkable achievement for him really.
"It will really lift the team and now Joe can concentrate on going further in this competition."
Khan won a silver medal at the Athens Olympics in 2004 after losing 30-22 to Cuban Mario Kindelan in the lightweight final.