3x+3y+6z=9

2x+y+3z=7

x+2y-z=-10

any one know the answer

3x + 3y + 6z = 9

2x + 1y + 3z = 7 ⇒ 6x + 6y + 8z = 6

1x + 2y - 1z = - 10 6x + 6y + 8z = 6

4z = 12

3x + 3y + 6z = 9 4 4

2x + 1y + 3z = 7 ⇒ 0x + 0y + 4z = 12 z = 3

1x + 2y - 1z = - 10 2x + y = - 2

2x + (-4) = - 2

2x - 4 = - 2

+ 4 + 4

2x = 2

2 2

x = 1

(x, y, z) = (1, - 4, 3)