Hello ,

If you fail in only one of the six subject of you class 12 boards examination you will be considered to be overall Passed and the subject in which you failed will be considered as the additional subject .You will have the opportunity to attempt the compartment exam if you want to (I would suggest you to attempt it as it might create some problem in future ).

If you fail in two or more subjects you will be considered as fail and will have to repeat class 12 .

Hope this helps.