SOLUTION: How do you solve the following systems of equations? 3x-2y+2z=-2 x+6y-2z=-2 x+2y=0 I really have no clue what I'm doing..

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Question 672933: How do you solve the following systems of equations?
3x-2y+2z=-2
x+6y-2z=-2
x+2y=0
I really have no clue what I'm doing..
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve the following systems of equations?
3x-2y+2z=-2
x+6y-2z=-2
x+2y=0
----
Rearrange:
x + 2y + 0 = 0
x + 6y - 2z = -2
3x- 2y + 2z = -2
-------------------
Subtract 1st from 2nd.
Subtract 3 times 1st from 3rd
-----
x + 2y + 0 = 0
0 + 4y - 2z = -2
0 - 8y + 2z = -2
-----
Add 2 times 2nd eq. to 3rd
x + 2y + 0 = 0
0 + 4y - 2z = -2
0 + 0 - 2z = -6
----------------------
z = 3
---
4y = 4
y = 1
----
x = -2
=================
Cheers,
Stan H.