SOLUTION: 3x-4z=-1 2y+3z=2 2x+3y=6

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Question 1152642: 3x-4z=-1
2y+3z=2
2x+3y=6
Found 2 solutions by MathLover1, MathTherapy:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

3x-4z=-1...........1
2y%2B3z=2...........2
2x%2B3y=6...........3
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3x-4z=-1......solve for z
3x%2B1=4z
z=%283x%2B1%29%2F4...........1a
2y%2B3z=2.....solve for z
z=2%281-y%29%2F3..........2a

from 1a and 2a we have

%283x%2B1%29%2F4=2%281-y%29%2F3.....solve for x
%283x%2B1%29%2F4=2%281-y%29%2F3.........cross multiply
3%283x%2B1%29=4%2A2%281-y%29
9x%2B3=8-8y....solve for x
9x=8-8y-3
9x=5-8y
x=%285-8y%29%2F9.........3a

2x%2B3y=6.........3, substitute+x
2%285-8y%29%2F9%2B3y=6....solve for y
2%285-8y%29%2B9%2A3y=6%2A9
10-16y%2B27y=54
11y=54-10
11y=44
y=4
go to
x=%285-8y%29%2F9.........3a, plug in y
x=%285-8%2A4%29%2F9
x=%285-32%29%2F9
x=+-27%2F9
x=+-3
go to
z=%283x%2B1%29%2F4...........1a, plug in x
z=%283%28-3%29%2B1%29%2F4
z=%28-9%2B1%29%2F4
z=-8%2F4
z=-2
solutions:
x+=+-3, y+=+4,+z+=+-2

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

3x-4z=-1
2y+3z=2
2x+3y=6
I'd advise you NEVER to consider using this woman's method to solve these equations!

It's a ridiculously "SAD" way to do these types of problems!