Question

5x-3y+2z=3
2x+4y-z=7
x-11y+4z=3

Answer 1

5x-3y+2z=3
2x+4y-z=7 multiply by 2 and assum with first equation
x-11y+4z=3

5x-3y+2z=3
4x+8y-2z=14
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9x+5y 0 =17

2x+4y-z=7 multiply by 4 and assum with 3rd equation

8x+14y-4z=28
x-11y+4z=3
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9x+3y 0 =31

9x+5y=17
9x+3y=31 multiply by -1 and assum

9x+5y=17
-9x-3y=-31
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0 2y= -14 so y= -14/2 = -7
y=-7

9x+5(-7)=17
9x-35=17
9x=52
x=52/9

2x+4y-z=7
2(52/9)+4(-7)-z=7
104/9 -28-z=7
104 -252 -9z =63
-148 -9z =63
-148 -63=9z
-211=9z
z= -211/9

x= 52/9
y= -7
z= -211/9