Question

Gunakan metode gabungan
2x+y+z=8
3x-y+2z=17
4x+2y-z=1

Answer 1

2x+y+z=8
3x-y+2z=17
(eliminasi z)
4x+2y+2z=16
3x-y+2z=17
_______________ _
×+3y = -1
(pers.a)

3x-y+2z=17
4x+2y-z=1
(eliminasi z)
3x-y+2z=17
8x+4y-2z=2
____________ +
11x+3y=19

(eliminasi menggunakan pers. a dan b)
x+3y=-1
11x+3y=19
____________ _
-10x = -20
x = 2

substitusi x ke pers. a
x+3y = -1
2 + 3y=-1
3y=-3
y= -1

substitusi x dan y ke pers awal
2x+y+z=8
2.2 + -1 + z = 8
z = 5