Question

Tentukan himpunan dari persamaan linier tiga variabel
x - y + 2z = 5
2x + y - z = 9
x - 2y + 3z = 3

[tolong bantuin ya ?]

Answer 1

•
x - y + 2z = 5 | x2 | 2x - 2y + 4z = 10
2x + y - z = 9 | x1 | 2x + y - z = 9
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⇔ -3y + 5z = 1
•
2x + y - z = 9 | x1 | 2x + y - z = 9
x - 2y + 3z = 3 | x2 | 2x - 4y + 6z = 6
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⇔ 5y - 7z = 3
•
-3y + 5z = 1 | x(-5) | 15y - 25z = -5
5y - 7z = 3 | x3 | 15y - 21z = 9
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⇔ -4z = -14
z = 14/4 
⇔z = 7/2
•
5y - 7z = 3
5y - 7(7/2) = 3
5y - 49/2 = 3
5y = 3 + 49/2
5y = (6+49)/2 
5y = 55/2
y = 55/2 x 1/5
⇔ y = 11/2
•
2x + y - z = 9
2x + 11/2 - 7/2 = 9
2x + 4/2 = 9
2x + 2 = 9
2x = 9-2
2x = 7
⇔ x = 7/2

HP = { 7/2 , 11/2 , 7/2}

Tolong dijadikan sebagai jawaban yang terbaik ya :)