Show that each of the following systems of linear equations is consistent and also find their

2x + 3y = 5


6x + 9y = 15

The above system of equations can be written as


or AX = B


Where A = B = and X =


|A| = 18 – 18 = 0


So, A is singular,Now X will be consistence if (Adj A)xB = 0


C11 = (– 1)1 + 1 9 = 9


C12 = (– 1)1 + 2 6 = – 6


C21 = (– 1)2 + 1 3 = – 3


C22 = (– 1)2 + 2 2 = 2


Also, adj A =


=


(Adj A).B =


=


Thus, AX = B will be infinite solution,


Let y = k


Hence,


2x = 5 – 3k or X =


x = 15 – 9k or X =


Hence, X = , Y = k


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