Answer:
- r1 +4×r3 ⇒ r1
- r2 -3×r3 ⇒ r2
Step-by-step explanation:
We note that the coefficient of y in equation (iii) is 1, so it is convenient to use that equation to eliminate y from the others.
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To eliminate the y-variable from equation (i), four times equation (iii) can be added to equation (i).
To eliminate the y-variable from equation (ii), three times equation (iii) can be subtracted from equation (i).
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The result of these operations would be ...
[tex]10x +6z = 28\quad\text{(iv)}\\\\-7x-9z=2\quad\text{(v)}[/tex]
