Science:Math Exam Resources/Courses/MATH152/April 2016/Question A 08/Solution 1
The given system of the linear equations can be represented by the augmented matrix:
Since elementary row operations do not change the solution to the linear system, we remove the entry in column 1 of row 2 by subtracting off -2 times the first row;
which is equivalent to
Therefore, from the second equation, we have .
And the third equation implies , so .
Finally, from the first equation, we obtain .
Therefore, the solution is .