Question
Solve the system of the following equations:
Solution
The given equations are
Put 
∴ given equations become
2a + 3b + 10c = 4
4a – 6b + 5c = 1
6a + 9b – 20c = 2
These equations can be written as
or 
Co-factors of the elements of first row of | A | are
i.e. 120 – 45, – (– 80 – 30), 36 + 36 i.e. 75, 110, 72 respectively.
Co-factors of the elements of second row of | A | are
i.e. – (– 60 – 90), – 40 – 60, – (18 – 18) i.e. 150, 100, 0 respectively.
Co-factors of the elements of third row of | A | are
i.e. 15 + 60, – (10 – 40), – 12 – 12 i.e. 75, 30, –24 respectively.
