Răspuns :
a)x=2y
(0,8x+1,2y )/ (x-y)=
=(0,8×2y+1,2y) / (2y-y)=
=(1,6y+1,2y )/ y=2,8
b)y=2x
(0,8x+1,2× 2x )/ x-2x=
=(0,8x+2,4x )/ -x=
=3,2x/-x=-3,2
(0,8x+1,2y )/ (x-y)=
=(0,8×2y+1,2y) / (2y-y)=
=(1,6y+1,2y )/ y=2,8
b)y=2x
(0,8x+1,2× 2x )/ x-2x=
=(0,8x+2,4x )/ -x=
=3,2x/-x=-3,2