Question 795658
2x+y+4z=16  Eqn 1
x+2y+2z=11  Eqn 2
3x-3y-2z= -9 Eqn 3
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Pick 1 one of the variables to eliminate.
I'll do z first
x+2y+2z=11  Eqn 2
3x-3y-2z= -9 Eqn 3
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4x - y = 2  Eqn A
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2x+ y+4z = 16  Eqn 1
6x-6y-4z= -18 Eqn 3 times 2
-------------------------------- Add
8x - 5y =-2  Eqn B
4x - y = 2  Eqn A
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Now it 2 equations in x & y
eliminate x or y in a similar manner