Kk tlng jwab kk, klw bisa kk

2x + 2y -z = 8. pers 1
3 – z = 10. pers 2
5x – 2y = 12. pers 3

dari pers 2
3 – z = 10
=> z = – 10 +3 = -7

substitusi ke pers 1
2x + 2y -z = 8
2x + 2y – (-7) =8
2x + 2y = 8 – 7= 1
2x + 2y = 1
2y = 1 – 2x

substitusi ke pers 3
5x – 2y = 12
=> – 2y = 12 – 5x
=> 2y = -12 + 5x
1 – 2x = – 12 + 5x
1+12 = 7x
x = 13/7 = 1 6/7

maka y
2y = 1 – 2(13/7)
2y = 1 – 26/7
2y = 7/7 – 26/7 = – 19/7
y = 1/2 ( -19/7)
= – 19/14
= -1 5/14

HP ( 1 6/7, – 1 5/14, -7)

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