Solve the linear systom of equations: (a)
x_(1)+2x_(2)+3x_(3)=6 3x_(1)-x_(2)-x_(3)=2 4x+3x_(2)-2x_(3)=4
(b)
x_(1)-2x_(2)+3x_(3)=5 3x_(2)+4x_(3)=10
(c)
3x_(2)+4x_(3)=7 2x_(1)+x_(2)-3x_(3)=0 3x_(1)+4x_(2)=7