Nilai ( x - y ) dari sistem persamaan linear x + y + z=2 3y -4z =-5 6z =3

x+y+x = 2

Cari nilai z
6z=3
z=3/6=1/2

Cari nilai y
3y-4z=-5
3y- (4 X 1/2) =-5
3y-2=-5
3y=-5+2
3y=-3
y=-1

Cari nilai x
x+y+z=2
x-1+1/2=2
x-1/2=2
x=2+1/2
x=2,5

6z=3
z=1/2

3y-4y=-5
3y-4(0,5)=-5
3y-2=-5
3y=-3
y=-1

x+y+z=2
(x)-1+1/2=2
x-1/2=2
x=5/2

jafi x-y=
(5/2)-(-1)
(5/2)+1
=7/2