# Math Help - Guassian elimination to solve system

1. ## Guassian 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!

2. Your answer works for the first equation, but for the second:

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

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