tentukan HP sistem persamaan linear 3 variabel dari 5x-y+2z=25 , 3x+2y-3z=16 , 2x-y+z=9

5x-y+2z=25     => dikali 2 => 10x-2y+4z=50
3x+2y-3z=16   => dikali 1 => 3x+2y-3z=16
                                             ---------------------    +
                                               13x    +z  = 66

 3x+2y-3z=16   => dikali 1 => 3x+2y-3z=16
2x-y+z=9          => dikali 2 => 4x-2y+2z=18
                                              ---------------------   +
                                                 7x    -z = 34

13x+z=66
7x-z=34
--------------  +
20x   = 100
x=5

7x-z=34
35-z=34
z=35-34
z=1

2x-y+z=9
10-y+1=9
11-y=9
y=2

Jadi:
x=5
y=2
z=1