yes / no
these lines from some TV series make me confused:
1. A: are we good?
B: nope, we are good.
and
2. A: I think it's such a terrific thing that you …
B: no, it is.
For answering 'are we good?', why is it 'no', not 'yes'? and how comes when you what to agree with someone, you say 'no, it is.' instead of ' yes, it is. '?

Question

yes / no
these lines from some TV series make me confused:
1. A: are we good?
    B: nope, we are good.
and 
2. A: I think it's such a terrific thing that you …
    B: no, it is.
For answering 'are we good?', why is it 'no', not 'yes'?  and  how comes when you what to agree with someone, you say 'no, it is.' instead of ' yes, it is. '?

Answer

I see, thank you very much.

Answer

You probably need to supply more context. For example:
A I was worried that you were mad at me. Are we good?
B “No, I’m not mad at you. We’re good.” Shortened to “No, we’re good “