How do i convince my parents to let me go to an avenged sevenfold concert?

At first, just casually mention the tour and that your friend is going. After that, then you can straight out ask them, and tell them that transport isn't a problem, and you'll have an adult with you, and you won't go off anywhere on your own. Then you can start with the reasons why you'd like to go (need to go), like it would be an experience to see them with their new drummer Aaron, so you can observe the chemistry. Another reason would be to look into zackys beautiful eyes ;) but anyway...you can promise to be on your best behavior, do extra chores and so on (maybe you won't like it, but i promise you, the gig will be worth it.). Once your parents see that you've put a lot of though and planning into this, they will most likely agree :) These are the things I normally do to get my dad to agree for me to go to gigs. I sincerely hope you are allowed to go, because Avenged Sevenfold are amazing live, and have an amazing stage presence.