selesaikan sistem persamaan linear tiga variabel berikut! 2x+y-z=2 x+2y+3z= 13 3x-y+z=8
Matematika
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Pertanyaan
selesaikan sistem persamaan linear tiga variabel berikut!
2x+y-z=2
x+2y+3z= 13
3x-y+z=8
2x+y-z=2
x+2y+3z= 13
3x-y+z=8
1 Jawaban
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1. Jawaban fatimah3085
2x + y - z = 2 |×1
x + 2y + 3z = 13 |×2
2x + y - z = 2
2x + 4y + 6z = 26
--------------------------(-)
- 3y - 7z = - 24 ...pers 1
x + 2y + 3z = 13 |×3
3x - y + z = 8
3x + 6y + 9z = 39
3x - y + z = 8
---------------------------(-)
7y + 8z = 31 ... pers 2
pers 1 & 2
- 3y - 7z = - 24 |×7
7y + 8z = 31 |×3
- 21y - 49z = - 168
21y + 24z = 93
---------------------------(+)
- 25z = - 75
z = 3
- 3y - 7z = - 24
- 3y - 7(3) = - 24
- 3y = - 24 + 21
- 3y = - 3
y = 1
2x + y - z = 2
2x + 1 - 3 = 2
2x = 2 + 2
x = 4 ÷ 2
x = 2
Hp = { 2,1,3}