4x+2y-3z=7 2x-3y+z=2 X+y-z=2

4x+2y-3z=7 |×1 |
2x-3y+z=2 |×2|
_____________
4x+2y-3z=7
4x-6y+2z=4
_________(-)
8y-5z=3..........(1)

2x-3y+z=2 |×1|
x + y -z =2 |×2|
___________
2x-3y+z=2
2x+2y-2z=4
__________(-)
-5y+3z=-2........(2)

8y-5z=3 |×3|
-5y+3z=-2 |×5|
__________
24y-15z=9
-25y+15z=-10
__________(+)
-y=-1
y = 1

-25y+15z=-10
-25(1)+15z=-10
-25 +15z=-10
15z = -10+25
15z = 15
z = 1

4x+2y-3z=7
4x+2(1)-3(1)=7
4x+2-3=7
4x-1=7
4x= 7+1
4x= 8
×= 2

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