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14 votes
14 votes
Solve the following system of equations algebraically

x+y-z=6
2x-3y+2z=-19
-x+4y-x=17

User Sivan
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1 Answer

25 votes
25 votes

Answer: {x,y,z}={-11/14,27/7,-41/14}

Explanation:

System of Linear Equations entered :

[1] x+y-z=6

[2] 2x-3y+2z=-19

[3] -x+4y-x=17

Equations Simplified or Rearranged :

[1] x + y - z = 6

[2] 2x - 3y + 2z = -19

[3] -2x + 4y = 17

Solve by Substitution :

// Solve equation [1] for the variable y

[1] y = -x + z + 6

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

[2] 2x - 3•(-x +z +6) + 2z = -19

[2] 5x - z = -1

// Plug this in for variable y in equation [3]

[3] -2x + 4•(-x +? +6) = 17

[3] -6x = -7

// Solve equation [2] for the variable z

[2] z = 5x + 1

// Plug this in for variable z in equation [3]

[3] -6x = -7

[3] 14x = -11

// Solve equation [3] for the variable x

[3] 14x = - 11

[3] x = - 11/14

// By now we know this much :

x = -11/14

y = -x+z+6

z = 5x+1

// Use the x value to solve for z

z = 5(-11/14)+1 = -41/14

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

y = -(-11/14)+(-41/14)+6 = 27/7

Solution :

{x,y,z} = {-11/14,27/7,-41/14}

User Littleguga
by
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