Question 89878
x+y+2z=11 now subtract the second equation:
-(x+y+3z=14)
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-z=-3 or z=3 answer.
x+2y-3=5 now subtract the first equation after replacing z by 3:
-(x+y+2*3=11)
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y-3+6=-6
y-3=0
y=3 answer.
x+3+2*3=11
x+3+6=11
x+9=11
x=11-9
x=2 answer.