5. Diketahui sistem persamaan linear

Penjelasan dengan langkah-langkah:

x + y – z = -3

x + 2y + z = 7

——————- –

y + 2z = 10

2x + y + z = 4

2x + 2y – 2z = -6

———————— –

y – 3z = -10

y + 2z = 10

y – 3z = -10

————— –

5z = 20

z = 20 ÷ 5 = 4

y + 2z = 10

y + 2 . 4 = 10

y = 10 – 8 = 2

x + y – z = -3

x + 2 – 4 = -3

x = -3 + 2

= -1

jadi, x + y + z = -1 + 2 + 4 = 5