2x-2y-2z =9 x-6y-3z =-28 3x+2y+z=16

2x-2y-2z=9....(1)
x-6y-3z=28.....(2)
3x+2y+z=16.....(3)

(1) & (2)
2x-2y-2z=9 ^¹ 2x-2y-2z=9
x-6y-3z=28 ^² 2x-12y-6z=58. =
14y+8z=157....(4)
(1) & (3)
2x-2y-2z=9 ^³ 6x-6y-6z=27
3x+2y+z=16 ^² 6x+4y+2z=42. =
-2y-4z=-15.....(5)
(4) &(5)
14y+8z=157 ^⁴ 56y+32z =628
-2y-4z=-15 ^8 16y-32z=-120. =
40y =628
y= 628 : 40 = 56 per 4 hasilnya 14.
y = 14.
X dan Y cari sendiri?