tentukan himupan penyesaian dari x-y+z= -4 , x+y+2z= -5, dan 3x-y-z= -6

jawab

(i)  x - y + z =- 4
(ii) x + y + 2z = - 5 |(+)
2x + 3z = -9 (iv)

(i) x- y + z= - 4
(iii) 3x - y- z= - 6  | (-)
-2x  + 2z = 2 (v)

(iv) dan (v)
2x + 3z = -9
-2x  + 2z = 2 | (+)
5z = - 7
z = -7/5

2x + 3z = - 9
2x + 3(-7/5) = -9
2x  - 21/5 = - 9
10x - 21 = - 45
10x = -24
x = - 12/5

x - y + z = - 4
-12/5  - y  - 7/5 =  -4
-12 - 5y - 7 = - 20
-19 - 5y = - 20
-5y=- 1
y = 1/5

(x,y,z) = (-12/5,  1/5, -7/5)