The plant is wild violet (viola paploniace) and spreads rapidly. It has a pretty flower but easily becomes a weed. I control it with 24D mixed with a sticker solution.
Most broadleaf weed killers work. But as said above the heavy stuff works best. You got the name head on over to home depot look at the bottles the hook up to your hose make sure your weed is listed on the back and follow the directions to a t