Question 1002143
Given the system of equations 
2x −3y  -9z=9
x  +0y + 3z=3
−3x+y−4z=−10
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Note:: x = -3z+3
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Substitute for "x" in rows 1 and 3::
2(-3z+3) -3y - 9z = 9
-3(-3z+3) + y - 4z = -10
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Simplify::
-3y -15z = 3
y + 5z = -1
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Modify::
y + 5z = -1
y + 5z = -1
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The system is dependent. 
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y = -5z-1
x = -3z + 3
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Cheers,
Stan H.

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