There flowers are growing profusely at the edge of a small lake in Arlington, Texas, zone 8b.
The plants at about 2 feet tall, and they have no scent.
Thank you for your help.

Foliage and flowers.



Foliage and flowers.




Close up of flower.

Helianthus?

Nodding Beggar-Ticks (Bidens cernua) . One of the showier species of Bidens.

Thank you Kent, you gave me the right clue. I checked on wildflower.org and Bidens cernua is not native to Texas.
But Bidens leavis is and it looks just just like the flowers by the lake.
https://www.wildflower.org/pla...
Thank you so much for your help.

This ID is solved, thank you Kent.

I'm happy you have an identification.
I had noticed that you said the plants were growing at a lake but I see the photo has them in pots; possibly in your greenhouse? If these are anything like the Bidens I brought home, please...deadhead religiously! Do not let the seeds escape. Beautiful plants but they do require a bit of management.

Thank you Greene, for the warning.
Actually I couldn't get close enough to the plants because they were in the water and the ground was very sloping, so I took some and stuck them in a pot to hold them up for the picture. They dried out soon after, so no problem.