SOLUTION: Please help me solve this using matrices: x + 2y - z = 2 2x - 2y + z = -1 6x +4y +3z = 5 Thank you so much, Lennie

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Question 150173: Please help me solve this using matrices:
x + 2y - z = 2
2x - 2y + z = -1
6x +4y +3z = 5
Thank you so much, Lennie
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
In Matrix notation, the problem is,

or simplified
[A][x]=[b]
[Ainv][A][x]=[Ainv][b]
[x]=[Ainv][b]
Find the inverse of matrix A, multiply by the right hand side to find the solution.
In this case,
[A]=
The inverse of [A] is,
[Ainv]=
Then the matrix multiplication is,
[x]=
x=%281%2F30%29%2810%2A2%2B%2810%29%28-1%29%2B0%285%29%29
x=%281%2F30%29%2820-10%29
x=%281%2F30%29%2810%29
x=1%2F3
y=%281%2F30%29%280%2A2%2B%28-9%29%28-1%29%2B%283%29%285%29%29
y=%281%2F30%29%289%2B15%29
y=%281%2F30%29%2824%29
y=4%2F5
z=%281%2F30%29%2820%2A2%2B%288%29%28-1%29%2B%28-6%29%285%29%29
z=%281%2F30%29%2840-8-30%29
z=%281%2F30%29%282%29
z=-1%2F15
Your solution matrix is then
[x]=