SOLUTION: 2x-y=8 x-6y-z=0 -6x+3y-9z+24 show solution of equation

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Question 258715: 2x-y=8
x-6y-z=0
-6x+3y-9z+24
show solution of equation
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Use the first equation to solve for y.
2x-y=8
y=2x-8
Now substitute into eq.2 and 3 for y.
x-6y-z=0+
x-6%282x-8%29-z=0
x-12x%2B48-z=0
-11x-z=-48
11x%2Bz=48
.
.
.
I assume it should be "=24"?
-6x%2B3y-9z=24+
-6x%2B3%282x-8%29-9z=24
-6x%2B6x-24-9z=24
-9z=48
highlight%28+z=-16%2F3%29
Now go back and substitute to find x and then y.
11x%2Bz=48
11x-%2816%2F3%29=48
33x-16=144
33x=160
highlight%28+x=160%2F33%29
and then
y=2x-8
y=2%28160%2F33%29-8
y=320%2F33-264%2F33
highlight%28+y=56%2F33%29