Question 1020197
Add {{{-2*R1}}} to {{{R2}}},
Add {{{-3*R1}}} to {{{R3}}},
{{{x+y+z=1}}}
{{{0x-3y+4z=4}}}
{{{0x-4y-z=-1}}}
Add {{{-(4/3)*R2}}} to {{{R3}}},
{{{x+y+z=1}}}
{{{0x-3y+4z=4}}}
{{{0x+0y-(19/3)z=(-19/3)}}}
So then from row 3,
{{{z=1}}}
and
{{{-3y+4=4}}}
{{{-3y=0}}}
{{{y=0}}}
and
{{{x+0+1=1}}}
{{{x=0}}}