SOLUTION: if x²+y²+z²-64/xy-yz-zx=-2 and x+y=3z,than value of z is?

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Question 896463: if x²+y²+z²-64/xy-yz-zx=-2 and x+y=3z,than value of z is?
Answer by Edwin McCravy(20056)   (Show Source): You can put this solution on YOUR website!






Since , .  Substituting:













Divide through by 4



Fctor



z-4 = 0;  z+4 = 0

  z = 4;    z = -4

Edwin
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