Question
Using matrices, solve the following system of equations:
2x – y + z = 0
x + y – z = 6
3x – y – 4 z = 7
Solution
The given equations are
2x – y + z = 0
x + y – z = 6
3x – y – 4z = 7
These equations can be written as
or 
Now 
Co-factors of the elements of first row of | A | are
i.e. – 5, 1, – 4 respectively.
Co-factors of the elements of second row of | A | are
i.e. – 5, – 11, – 1 respectively.
Co-factors of the elements of third row of | A | are
i.e. 0, 3, 3 respectively.
