Question

3x+y-4z=-22 2x+3y+4z=32 x-y+2z=16

Answer 1

Answer: x=-1, y=2, z=-3

Step-by-step explanation:

[1]    2x + 3y - 4z = 16

  [2]    -x + 2y - z = 8

  [3]    2x - y - 2z = 2

Solve by Substitution :

Solve equation [3] for the variable  y

 [3]    y = 2x - 2z - 2

Plug this in for variable  y  in equation [1]

    2x + 3•(2x-2z-2) - 4z = 16

    8x - 10z = 22

Plug this in for variable  y  in equation [2]

    -x + 2•(2x-2z-2) - z = 8

      3x - 5z = 12

Solve equation [2] for the variable  x

 3x = 5z + 12

     x = 5z/3 + 4

Plug this in for variable  x  in equation [1]

   8•(5z/3+4) - 10z = 22

    10z/3 = -10

    10z = -30

Solve equation for the variable  z

    10z = - 30

   z = - 3

By now we know this much :

   x = 5z/3+4

   y = 2x-2z-2

   z = -3

Use the  z  value to solve for  x

   x = (5/3)(-3)+4 = -1

Use the  x  and  z  values to solve for  y

 y = 2(-1)-2(-3)-2 = 2