Round up is nasty stuff. Don’t waste your money on that poison. Salt may do the same job for you! This method prevents other plants from growing too so you definitely don’t want to use this anywhere that you’ll be wanting to grow flowers, veggies, plants or shrubs in the future. So be careful that you don’t overdo it so that the salt doesn’t leak to places you actually want to grow things in. Here’s the source link that explains the detailed process for you.
How to use salt to control weeds! – The Creek Line House
So in short you can control weed by salting the unwanted weed areas, you should start early spring, as soon as you see weed growing to keep the weed under control, also you don’t might need to use water with the salt for resistant weeds.