Question 366380
1.{{{2x-y+4z=33}}}
2.{{{5x+3y-2z=-62}}}
3.{{{3x-4y+z=42}}}
Multiply eq. 2 by 2 and add to eq. 1,
{{{2x-y+4z+10x+6y-4z=33-124}}}
4.{{{12x+5y=-91}}}
Multiply eq. 3 by 2 and add to eq. 2,
{{{5x+3y-2z+6x-8y+2z=-62+84}}}
5.{{{11x-5y=22}}}
Add eq. 4 and eq 5,
{{{12x+5y+11x-5y=-91+22}}}
{{{23x=-69}}}
{{{highlight( x=-3)}}}
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Then from eq. 4,
{{{-36+5y=-91}}}
{{{5y=-55}}}
{{{highlight( y=-11)}}}
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Then from eq. 1,
{{{2(-3)-(-11)+4z=33}}}
{{{-6+11+4z=33}}}
{{{4z=28}}}
{{{highlight( z=7)}}}