Question

I'm learning about determinants and cramer's rule, and I'm trying to figure out how to find the matrix in the problems but I'm not sure how.

Answer 1

Given a matrix,

a b

c d

the determinant would be ad - bc

Fof the first matrix, the determinant would be

`\begin{gathered} (3)/(2)*(1)/(4)-(1)/(2)*-(1)/(4) \\ =\text{ }(3)/(8)+(1)/(8) \\ The\text{ denominator is the same. We just add the numerator. It becomes} \\ (4)/(8) \\ =\text{ }(1)/(2) \end{gathered}`

For the second matrix, the determinanat would be

`\begin{gathered} -\text{ 3}*-\text{ 6 - (- 1 }*-\text{ 4)} \\ =\text{ 18 - 4} \\ =\text{ 14} \end{gathered}`