How do I convince my parents to let me get a dog?

I'm 14 years old and have two cats and one dog. I feed the cats and the dog and walk the dog at least twice a day. I give them no reason not to trust me but they still say no. I've even been saving to buy a puppy myself. What can I do/say to convice them to let me get one?How do I convince my parents to let me get a dog?
Find out what breed you want and get lots of info on that breed, then tell them that you want one. Then show them the information. If that doesn't work then ask them why you can't have one. If they can't afford another pet tell them that you will pay for it. If they think you aren't responsible enough do extra chores around the house without getting paid. After you do all that and they still say no tell them about the dogs in shelters and they all need homes.How do I convince my parents to let me get a dog?
hey u could always use animal psycology on them lol i mean there are 2 cats ...so each cat finds herself in a suitable environment ....while the dog is alienated in a foreign territory dominated by cats ...lol i sudyied some of that myself so it's scientifically proven ...better yet tell them the dog will have to see a vet beacuse of it and they're gonna have to pay for it ...hope this helps ...peace out
prove to them that youre responsible enough and deserve one. make a presentation stating all the facts and sit them down %26amp;%26amp; show them and explain it all to them. if that doesnt work then idk what else to tell you lol.