Question

The following simultaneous equations are given in base two 11x + 10y = 1100
101x - y =111
Find the value of x and y

Answer 1

multiply the 2nd by 10
1010x - 10y = 1110
add to the first

1010x - 10y = 1110
11x + 10y = 1100
...............................
1101x = 11010
x = 10

in the 1st
110 +10y = 1100
10y = 1100-110 = 110
y = 11

Answer 2

I DON'T UNDERSTAND

Answer 3

When I calculated1010+11 I got something else