Hello everyone,
I am sorry if this has been posted, but I don't know what to search for or how to otherwise figure out what this is.

I live in Maryland, near Washington DC and this thing has taken over my lawn over the past couple of weeks. I've sprayed a product called Sedgehammer a few times, since it kind of looks like a nutsedge and it took care of a similar looking weed, but this one won't respond to it, or other lawn weed control chemicals.

Again, sorry if this is misposted, and thank you for any help in identifying or recommendations for treatment.