two questions all the same Solve the system of equations x

two questions all the same Solve the system of equations

x - 2y - z = 4   ------   -x + 6y - 3x = -12  ----- 2x - 11y + 5z = 22

next

x + y + z - w = 6 ----- 4x + y -z + w = 10 ----- x - 3y + 3z + w = 4 ------ -x - y + z + 4w = 6

Solution

first: no solutions exist

second:

x=2,

y=3,

z=3,

w=2