Answer is (1, 2, -6)
x + 3y + z = 1 -------> first equation
2x – y – z = 6 -------> second equation
5x + y + z = 1 -------> third equation
Add second and third equation
2x – y – z = 6 -------> second equation
5x + y + z = 1 -------> third equation
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7x = 7 (divide by 7 on both sides)
So x= 1
Now we add first and second equations
x + 3y + z = 1 -------> first equation
2x – y – z = 6 -------> second equation
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3x +2y = 7
We already got x=1, replace it in the above equation
3(1) + 2y = 7
3 + 2y = 7 (subtract 3)
2y = 4 (divide both sides by 2)
So y =2
Now plug in the values in first equation
x + 3y + z = 1 -------> first equation
1 + 3(2) + z = 1
7 + z = 1 (subtract 7 from both sides)
z = -6
Answer is (1, 2, -6)
