SOLUTION: 2x + y – z = 5 2x + 8y + 4z = 32 30x + 12y – 4z = 24

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Question 1054679: 2x + y – z = 5 2x + 8y + 4z = 32 30x + 12y – 4z = 24
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.2x+%2B+y-+z+=+5
2.2x+%2B+8y+%2B+4z+=+32
3.30x+%2B+12y+-4z+=+24+
Multiply 1 by 4 and add to 2,
8x%2B4y-4z%2B2x%2B8y%2B4z=20%2B32
10x%2B12y=52
4.5x%2B6y=26
Add 2 and 3,
2x%2B8y%2B4z%2B30x%2B12y-4z=32%2B24
32x%2B20y=56
5.8x%2B5y=14
Multiply 4 by 5 and 5 by -6 and add together,
25x%2B30y-48x-30y=130-84
-23x=46
x=-2
Then,
5%28-2%29%2B6y=26
6y=36
y=6
and
2%28-2%29%2B6-z=5
-4%2B6-z=5
-z=3
z=-3