Question
Use matrix method to solve the following system of equations:
2x – y – z = 1
x + y + 2z = 1
3x – 2y – 2z = 1
Solution
The given equations are
2 x – y – z = 1
x + y + 2z = 1
3x – 2y – 2z = 1
These equations can be written as
or 
Co-factors of the elements of first row of | A | are
i.e. 2, 8, – 5 respectively
Co-factors of the elements of second row of | A | are
i.e. 0, – 1, 1 respectively
Co-factors of the elements of third row of | A | are
