How Do You Correctly Subtract Using 1's and 2's Complement in Binary?

[ineedhelpnow]

(Wave)
i have to subtract binary numbers using the method where you take the 1's complement and then the 2's complement. but I am doing something wrong.

say for example 11-1. take 1's complement of 1 which is 0 and then take the 2's complement by adding 1 so 0+1=1 and now you go back and add this number to 11.

11+1=100 and you ignore the first value (1) and you end up with 00 and i know its TOTALLY messed up i just don't know where i went wrong. i know the actual answer should be 10 (or 2 in decimal)

thanks for any help

 

[ineedhelpnow]

oh i see what i did wrong. it needs to be of an equal number of bits so 1 becomes 01 AND THEN i take the 1's comp