was able to/could

[rajeshmalladi]

I had some free time yesterday, I was able to help her at that time.
I had some free time yesterday, I could help her at that time.


Difference between the above sentences.

Thank you so much,
Rajesh.

[Rusty]

I had some free time yesterday, I was able to help her at that time.
I had some free time yesterday, I could help her at that time.
(The sentences have the same meaning).