Решить систему способом Гаусса:
2x1 + 2x2 - x3 + x4 = 4,
4x1 + 3x2 - x3 + 2x4 = 6,
8x1 + 5x2 - 3x3 + 4x4 = 12,
3x1 + 3x2 - 2x3 + 2x4 = 6.

2x1+2x2-x3+x4=4,

-x2+x3=-2,

-3x2+x3=-4,

-0,5x3+0,5x4=0.

2x1+2x2-x3+x4=4,

-x2+x3=-2,

-2x3=2,

x3=x4.

2x1+2x2-x3+x4=4,

-x2+x3=-2,

x3=-1,

x4=-1.

2x1+2x2-x3+x4=4,

x2=1,

x3=-1,

x4=-1.

x1=1,

x2=1,

x3=-1,

x4=-1.