2x+3y-z=4 converting this into an augmented matrix and into echelon form

4x-2y+3z=-7

-6x+7y-7y=3

=

[1 1.5 -.5 2]

[0 1 -.8 2.2]

[0 0 1 8.9]

the answer i got was x= -7.5 y=9.3 z= 8.9

anyone care to solve this and check my answer?

many thanks!

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- Mar 23rd 2009, 08:06 PMSåxonGuassian elimination to solve system
2x+3y-z=4 converting this into an augmented matrix and into echelon form

4x-2y+3z=-7

-6x+7y-7y=3

=

[1 1.5 -.5 2]

[0 1 -.8 2.2]

[0 0 1 8.9]

the answer i got was x= -7.5 y=9.3 z= 8.9

anyone care to solve this and check my answer?

many thanks! - Mar 24th 2009, 02:31 AMShowcase_22
Your answer works for the first equation, but for the second:

$\displaystyle 4(-7.5)-2(9.3)+3(8.9)=-21.9 \neq -7$

Check your matrix in RRF, it doesn't look right....