Question 1019542
{{{x+y+z=7}}}
{{{x+3z=7}}}
{{{3x+y+z=12}}}
So then,
{{{A=(matrix(3,3,
1,1,1,
1,0,3,
3,1,1))}}}
{{{abs(A)=6}}}
.
.
{{{A[x]=(matrix(3,3,
7,1,1,
7,0,3,
12,1,1))}}}
{{{abs(A[x])=15}}}
.
.
{{{A[y]=(matrix(3,3,
1,7,1,
1,7,3,
3,12,1))}}}
{{{abs(A[y])=18}}}
.
.
{{{A[z]=(matrix(3,3,
1,1,7,
1,0,7,
3,1,12))}}}
{{{abs(A[z])=9}}}
.
.
{{{x=abs(A[x])/abs(A)=15/6=5/2}}}
{{{y=abs(A[y])/abs(A)=18/6=3}}}
{{{z=abs(A[z])/abs(A)=9/6=3/2}}}