Question

c) (x +2y - 3z=9
3x - y + 4z = -5
2x + y + z = 0​

Answer 1

Resposta:

x + 2y - 3z = 9 (-) 2x + y + z = 0

- x + y - 4z = 9 (+) 3x - y + 4z = - 5

2x = 4

x = 2

2 + 2y - 3z = 9 -> 2y - 3z = 7

4 + y + z = 0​ -> y + z = -4

y = -4 - z -> 2*(-4-z)-3z = 7

-8 -5z = 7 -> 15

z = -3

y = -1