We perform the Gauss-Jordan elimination
#((2,5,-2,14),(5,-6,2,0),(4,-1,3,-7))#
Exchange #R2 harr R1#
#((5,-6,2,0),(2,5,-2,14),(4,-1,3,-7))#
Divide #R1# by #5#
#((1,-1.2,0.4,0),(2,5,-2,14),(4,-1,3,-7))#
#R2 harr R2-2R1#
#((1,-1.2,0.4,0),(0,7.4,-2.8,14),(4,-1,3,-7))#
#R3 harr R3-4R1#
#((1,-1.2,0.4,0),(0,7.4,-2.8,14),(0,3.8,1.4,-7))#
#R2 harr (R2)/7.4#
#((1,-1.2,0.4,0),(0,1,-0.378,1.892),(0,3.8,1.4,-7))#
#R3 harr R3-3.8R2#
#((1,-1.2,0.4,0),(0,1,-0.378,1.892),(0,0,2.838,-14.189))#
#R3 harr (R3)/2.838#
#((1,-1.2,0.4,0),(0,1,-0.378,1.892),(0,0,1,-5))#
#R1 harr R1-0.4R3#
#((1,-1.2,0,2),(0,1,-0.378,1.892),(0,0,1,-5))#
#R2 harr R2+0.378R3#
#((1,-1.2,0,2),(0,1,0,0),(0,0,1,-5))#
#R1 harr R1+1.2R2#
#((1,0,0,2),(0,1,0,0),(0,0,1,-5))#