<PRE><B>Question 576405</B>
3w = 6


w = 6/3


w = 2

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2z + 2w = -12


2z + 2(2) = -12


2z+4 = -12


2z = -12-4


2z = -16


z = -16/2


z = -8


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y + z - w = 4


y + (-8) - 2 = 4


y - 10 = 4


y = 4 + 10


y = 14


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x + 2y - 2z + 4w = 1


x + 2(14) - 2(-8) + 4(2) = 1


x + 28 + 16 + 8 = 1


x + 52 = 1


x = 1-52


x = -51


So the solution is (-51, 14, -8, 2)</PRE>