Question 892453
3/8,-3/5,33/80
4,4,23/35

divide row 1 by 3/8
1,-24/15,264/240
4,4,23/35

add  down (-4/1) *row 1 to row 2
1,-8/5,11/10
0,52/5,-1310/350

divide row 2 by 52/5
1,-8/5,11/10
0,1,-655/1820

We now have the value for the last variable.
We will work our way up and get the other solutions.

add up  (8/5) *row 2 to row 1
1,0,9540/18200
0,1,-131/364

final
1,0,477/910
0,1,-131/364

1,0,477/910 = 0.52417582
0,1,-131/364 = -0.35989011
"477/910","-131/364"
(477/910,-131/364)