SOLUTION: Please help me with this question. The directions: solve each system by elimination. 3x-y+z=3 X+y+2z=4 X+2y+z=4 I solved the first step which is: 3x-y+z=3 +(x+2y+z

Algebra ->  Equations -> SOLUTION: Please help me with this question. The directions: solve each system by elimination. 3x-y+z=3 X+y+2z=4 X+2y+z=4 I solved the first step which is: 3x-y+z=3 +(x+2y+z      Log On


   



Question 776418: Please help me with this question.
The directions: solve each system by elimination.
3x-y+z=3
X+y+2z=4
X+2y+z=4
I solved the first step which is:
3x-y+z=3
+(x+2y+z=4)= 4x+3z=7
X+y+2z=4
2(x+2y+z=4)= 2x+2z=8
And I'm stuck on the rest. Please help, thank you!

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve each system by elimination.
---------------
X+y+2z=4
X+2y+z=4
3x-y+z=3
-----
Subtract 1st from 2nd:::
Subtract 3 times 1st from 3rd:::
---------------------------------
X+y+2z=4
0+y-z = 0
0-4y-5z=-9
-----------
Add 4 times 2nd to 3rd:::
X+y+2z=4
0+y-z = 0
0+0-9z= -9
-------
Solve 3rd for "z":
z = 1
-----
Solve 2nd for "y":
y-1 = 0
y = 1
-------------------
Solve 1st for "x":
x + y + 2z = 4
x + 1 + 2 = 4
x = 1
-----------------------
Solution:
x = 1 ; y = 1 ; z = 1
===========================
Cheers,
Stan H.
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