Question 351940
{{{T1 = (10+20+T2+T3)/4}}}
{{{4T1=30+T2+T3}}}
{{{4T1-T2-T3=30}}}
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{{{T2 = (T1+20+40+T4)/4}}}
{{{4T2=T1+T4+60}}}
{{{-T1+4T2-T4=60}}}
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{{{T3 = (10+T1+T4+30)/4}}}
{{{4T3=T1+T4+40}}}
{{{-T1+4T3-T4=40}}}
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{{{T4 = (T3+T2+40+30)/4}}}
{{{4T4=T2+T3+70}}}
{{{-T2-T3+4T4=70}}}
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[A]={{{(matrix(4,4,4,-1,1,0, -1,4,0,-1,-1,0,4,-1,0,-1,-1,4))}}}
[T]={{{(matrix(4,1,T1,T2,T3,T4))}}}
[b]={{{(matrix(4,1,30,60,40,70))}}}
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[A][T]=[b]