SOLUTION: PLEASE HELP ASAP!! Solve the system of equations using Gauss- Jordan row reduction. You can put the matrix in row-echelon form ( with zeros in the lower left triangle) and then

Algebra ->  Finance -> SOLUTION: PLEASE HELP ASAP!! Solve the system of equations using Gauss- Jordan row reduction. You can put the matrix in row-echelon form ( with zeros in the lower left triangle) and then       Log On


   

Question 1073731: PLEASE HELP ASAP!!
Solve the system of equations using Gauss- Jordan row reduction. You can put the matrix in row-echelon form ( with zeros in the lower left triangle) and then use back substitution if you wish.
x+y+6z=4
x-y+2z=2
x +2z=0
Found 2 solutions by josgarithmetic, Fombitz:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Notice that the second and third equations both contain x+2z.

x+y+6z=4
(x+2z)-y=2
(x+2z)=0

Substitute for x+2z into the second equation.
0-y=2
y=-2-----one variable solved
.
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Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
%28matrix%283%2C4%2C%0D%0A1%2C1%2C6%2C4%2C%0D%0A1%2C-1%2C2%2C2%2C%0D%0A1%2C0%2C2%2C0%29%29
Replace R3 with R2-R3
%28matrix%283%2C4%2C%0D%0A1%2C1%2C6%2C4%2C%0D%0A1%2C-1%2C2%2C2%2C%0D%0A0%2C-1%2C0%2C2%29%29
Replace R2 with R1-R2,
%28matrix%283%2C4%2C%0D%0A1%2C1%2C6%2C4%2C%0D%0A0%2C2%2C4%2C2%2C%0D%0A0%2C-1%2C0%2C2%29%29
Replace R3 with R2+2R3,
%28matrix%283%2C4%2C%0D%0A1%2C1%2C6%2C4%2C%0D%0A0%2C2%2C4%2C2%2C%0D%0A0%2C0%2C4%2C6%29%29
So then,
4z=6
Solve for z and work backwards to get x and y.