x=y-2z, 2y=x+3z+1,z=2y-2x-3,solve by elimination method
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System of Linear Equations entered :
[1] x=y-2z
[2] 2y=x+3z+1
[3] z=2y-2x-3
Equations Simplified or Rearranged :
[1] x - y + 2z = 0
[2] -x + 2y - 3z = 1
[3] 2x - 2y + z = -3
Solve by Substitution :
// Solve equation [3] for the variable z
[3] z = -2x + 2y - 3
// Plug this in for variable z in equation [1]
[1] x - y + 2•(-2x+2y-3) = 0
[1] -3x + 3y = 6
// Plug this in for variable z in equation [2]
[2] -x + 2y - 3•(-2x+2y-3) = 1
[2] 5x - 4y = -8
// Solve equation [2] for the variable x
[2] 5x = 4y - 8
[2] x = 4y/5 - 8/5
// Plug this in for variable x in equation [1]
[1] -3•(4y/5-8/5) + 3y = 6
[1] 3y/5 = 6/5
[1] 3y = 6
// Solve equation [1] for the variable y
[1] 3y = 6
[1] y = 2
// By now we know this much :
x = 4y/5-8/5
y = 2
z = -2x+2y-3
// Use the y value to solve for x
x = (4/5)(2)-8/5 = 0
// Use the x and y values to solve for z
z = -2(0)+2(2)-3 = 1