tentukan HP dari: 2x+5y+4z=28 3x-2y+5z=19 6x+3y-2z=4

2x + 5y + 4z = 28. x1
6x + 3y - 2z = 4. x2
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2x + 5y + 4z = 28
12x + 6y - 4z = 8
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14x + 11y = 36

2x + 5y + 4z = 28. x5
3x - 2y + 5z = 19. x4
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10x +25y + 20z = 140
12x - 8y + 20z = 76
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-2x + 33y = 64

14x + 11y = 36. x3
-2x + 33y = 64. x1
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42x + 33y = 108
-2x + 33y = 64
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44x = 44
x = 1

14x + 11y = 14(1) +11y = 36
11y = 22
y = 2

6x + 3y -2z = 6(1) + 3(2) - 2z = 4
12 - 2z = 4
-2z = -8
z = 4