8x÷(14)y=1
(23)x÷(2−2)y=20
23x−(−2y)=20
implies3x+2y=0....(1)
log2(x−2y)=1
x−2y=21=2.....(2)
Solving equations 1 and 2,
x=12,y=−34
(x−y)=12−−34=54