Question

(1).Write the eight-bit 2’s complement
representation of (-23) base10

(2).What is the first thing you must do in order to
solve the subtraction problem 11 base10 – 4 base10 using
2’s compliment.

(3).What is the general technique for subtracting
binary numbers using 2’s compliment.

Answer 1

23 = 00010111
so, for -23, swap the bits and add 1: 11101000+1 = 11101001

This gives a good hint for the other parts.