Question 879786
{{{x-2y+3z=5}}}
{{{4x+3y+4z=7}}}
{{{x+y-z=-4}}}
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{{{(matrix(3,3,1,-2,3,4,3,4,1,1,-1))*(matrix(3,1,x,y,z))=(matrix(3,1,5,7,-4))}}}
Use Cramer's rule,
{{{A=(matrix(3,3,1,-2,3,4,3,4,1,1,-1))}}}
{{{abs(A)=-20}}}
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{{{A[x]=(matrix(3,3,5,-2,3,
                    7,3,4,
                    -4,1,-1))}}}
{{{abs(A[x])=-20}}}
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{{{A[y]=(matrix(3,3,1,5,3,
                    4,7,4,
                    1,-4,-1))}}}
{{{abs(A[y])=-20}}}
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{{{A[z]=(matrix(3,3,1,-2,5,
                    4,3,7,
                    1,1,-4))}}}
{{{abs(A[z])=-20}}}
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{{{x=abs(A[x])/abs(A)=40/(-20)=-2}}}
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{{{y=abs(A[y])/abs(A)=-20/(-20)=1}}}
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{{{z=abs(A[z])/abs(A)=-60/(-20)=3}}}