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Question

Correct option?

Comments

if u have any doubt see this link

https://en.wikipedia.org/wiki/Cramer's_rule.// this is better source 

Answer 1

In cramer's rule 

Consider a system of n linear equations for n unknowns, represented in matrix multiplication form as follows:

where the n × n matrix A has a nonzero determinant, and the vector  is the column vector of the variables. Then the theorem states that in this case the system has a unique solution, whose individual values for the unknowns are given by:

.

here coeffiecent matrix "A' determeninant should be nonzero.

so option is C.