They're all agreed in a positive way (4)
I believe the answer is:
ayes
'they're all agreed' is the definition.
I don't know anything about this answer so I can't judge whether this works.
'a positive way' is the wordplay.
I cannot quite understand how this works, but
'a' is found in the answer.
'positive' could be 'yes' and 'yes' is located in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
'in' acts as a link.
Can you help me to learn more?
(Other definitions for ayes that I've seen before include "Sounds of agreement" , "Nautical affirmatives" , "Voting assents" , "Those voting for the motion" , "Positive votes" .)