Upon arrival, customer informed me that her back bathroom master bathroom was backing up whenever she flushed the toilet into the shower. Customer said she just bought the house very recently and that the master bedroom was an ad on. The rest of the house was functioning properly as far as drainage and it was only the back bathroom that was having an issue. I advised customer that most likely it was a mainline stoppage and I was gonna need to access the roof to the vent connected to that bathroom and snake the drain. customer agreed so I access the roof and ran 75 feet of K 60 reel into the drain. I also ran 45 feet into the main 3” vent . after retrieving the snake, I went and tested. The bathroom for any stoppages, and the toilet was flushing perfectly, and the shower was draining perfectly. I advise customer I was going to run a camera just to make sure that the line was clear and after doing so I determine that the line was perfectly clear.