Simtem persamaan linear tiga variabel X-4y+ z =6 2x+y-2z=-1 3x+2y-2z=-2

x-4y+z=6......(1)
2x+y-2z=-1....(2)
3x+2y-2z=-2.....(3)
pers (1) x 2=> 2x-8y+2z=12....(..1')
per(2) + (1')=> 4x-7y=11....(4)
pers(2)-(3)=> -x-y=-3.....(5)
pers(5)x 4=> -4x-4y =-12......(5')
(4)+(5')... -11y= -1
y= 1/11
subs ke (5)... -x -1/11=-3
-x = -3+1/11
-x = -32/11
x= 32/11
32/11-4(1/11)+z =6
32/11-4/11+z =6
28/11 +z =6
z = 6-28/11
z= 66/11-28/11=38/11