Question

Please help me solve this 3 step equation for algebra 2 ASAP

Answer 1

Answer:

Step-by-step explanation:

x-3y-z=-9;-2x+y+2z=3;2x+y+3z=8

Solution :

{x,y,z} = {1,3,1}

System of Linear Equations entered :

  [1]    x - 3y - z = -9

  [2]    -2x + y + 2z = 3

  [3]    2x + y + 3z = 8

Solve by Substitution :

// Solve equation [3] for the variable  y

 [3]    y = -2x - 3z + 8

// Plug this in for variable  y  in equation [1]

  [1]    x - 3•(-2x-3z+8) - z = -9

  [1]    7x + 8z = 15

// Plug this in for variable  y  in equation [2]

  [2]    -2x + (-2x-3z+8) + 2z = 3

  [2]    -4x - z = -5

// Solve equation [2] for the variable  z

 [2]    z = -4x + 5

// Plug this in for variable  z  in equation [1]

  [1]    7x + 8•(-4x+5) = 15

  [1]    -25x = -25

// Solve equation [1] for the variable  x

  [1]    25x = 25

  [1]    x = 1

// By now we know this much :

   x = 1

   y = -2x-3z+8

   z = -4x+5

// Use the  x  value to solve for  z

   z = -4(1)+5 = 1

// Use the  x  and  z  values to solve for  y

 y = -2(1)-3(1)+8 = 3

Solution :

{x,y,z} = {1,3,1}