Binary Subtraction

To subtract two binary numbers:

Make the number you want to subtract negative (using Two's Compliment), then add it to the original number.

E.g: 25-49.

 25= 00011001
49 = 00110001
inverse = 11001110
+1 = 11001111
-49 = 11001111

25+(-49) = 00011001+11001111 
25+(-49) = 11101000

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