New member in search of knowledge and friends

Hello, my name is Justin. I have two older "puppies." Both of them are around 6 years old (rescue dogs). One is for sure a Border Collie/Aussie mix, and the other one I really don't know lol. I was told she is a German Shepherd/Black lab mix which Im having a hard time buying. I see a lot of dogs that look like her but nobody Ive spoken to has an explanation for their dog either aside from "mutt" lol. I just wanted to say hello to everyone here and introduce myself. Im here mostly to learn how to keep my aussie/collie dogs hair in tact and keep it from matting so bad, but I LOVE dogs and love learning so Im sure this will be a great forum to experience.