Question
Using matrices, solve the following system of linear equations:
2x + y + z = 7
x – y – z = – 4
3x + 2y + z = 10
Solution
The given equations are
2x + y + z = 7
x – y – z = – 4
3x + 2y + z = 10
These equations can by written as
Co-factors of the elements of first row of | A | are
i.e. – 1 + 2, – (1 + 3), 2 + 3 i.e. 1, – 4, 5 respectively.
Co-factors of the elements of second row of | A | are
i.e. – (1 – 2), 2 – 3, – (4 – 3) i.e. 1, – 1, –1 respectively.
Co-factors of the elements of third row of | A | are
i.e. – 1 + 1, – (2 – 1), – 2 – 1 i.e. 0, 3, – 3 respectively.
