SOLUTION: 12x+6y+7z=-35 7x-5y-6z=200 x+y=-10

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Question 1050204: 12x+6y+7z=-35
7x-5y-6z=200
x+y=-10
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Use Cramer's rule,
A=%28matrix%283%2C3%2C%0D%0A12%2C6%2C7%2C%0D%0A7%2C-5%2C-6%2C%0D%0A1%2C1%2C0%29%29
abs%28A%29=120
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.
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abs%28A%5Bx%5D%29=1200
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abs%28A%5By%5D%29=-2400
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.
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abs%28A%5Bz%5D%29=-600
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.
.
SO then,
x=abs%28A%5Bx%5D%29%2Fabs%28A%29=1200%2F120=10
y=abs%28A%5By%5D%29%2Fabs%28A%29=-2400%2F120=-20
z=abs%28A%5Bz%5D%29%2Fabs%28A%29=-600%2F120=-5