Question 389508
2x - y + 3z = 8......................1
x - 6y - z = 0.......................2
-6x + 3y - 9z = 24 ..................3

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select (1) &(2) eliminate x
select (2)&(3) eliminate x
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Then solve for y & z
multiply (2) by -2 and add to (1)

-2x+12y+2z=0
Add
+11y+5z=8......................(3)
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consider (2)&(3) eliminate x
multiply (2)by 6 and add to (3)
6x-36y-6z=0
add
-33y-7z=24.....................(4)
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multiply (3) by 3 & add to 4
33y+15z=24
add
+8z=48
{{{(highlight(z=6))}}}
plug z= 6 in (3)
11y+5*6=8
11y+30=8
11y=-22
{{{(highlight(y=-2))}}}
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plug y & z to get x
2x - y + 3z = 8......................1
2x+2+18=8
2x+20=8
2x=-12
{{{(highlight(x=-6))}}}
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