SOLUTION: I need assistance on solving systems of equations in three variables, by elimation. The question is 2x-y+Z=5 6X+3Y-2Z=10 X-2Y+3Z=5. I'm not sure how to begin this, I know you n

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Question 128698:
I need assistance on solving systems of equations in three variables, by elimation. The question is 2x-y+Z=5 6X+3Y-2Z=10 X-2Y+3Z=5. I'm not sure how to begin this, I know you need to elimate a variable. Can I lines the first and second equation and elimate the y variable? thanks
Answer by checkley71(8403) (Show Source):
You can put this solution on YOUR website!
2X-Y+Z=5 MULTIPLY THIS EQUATION BY 3 & ADD IT TO THE NEXT EQUATION
6X-3Y+3Z=15
6X+3Y-2Z=10
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12X+Z=25 OR Z=25-12X NOW MULTIPLY TH SECOND EQUATION BY2 & THE THIRD EQUATION BY 3 & ADD THEM:
12X+6Y-4Z=20
3X-6Y+9Z=15
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15X+5Z=35 NOW REP[LACE Z WITH(25-12X) & SOLVE FOR X
15X+5(25-12X)=35
15X+125-60X=35
-45X=35-125
-45X=-90
X=-90/-45
X=2 ANSWER.
Z=25-12*2
Z=24-24
Z=1 ANSWER.
2*2-Y+1=5
4-Y+1=5
-Y=5-1-4
-Y=0
Y=0 ANSWER.