if a matrix [9 x-6] is singular find x [3 x] - Maths - Matrices

Question

if a matrix [9 x-6] is singular find x
[3 x]

Aakash Sharma · Accepted Answer

Given : $[\begin{matrix} 9 & x - 6 \\ 3 & x \end{matrix}]$ is a singular matrix $\Rightarrow | \begin{matrix} 9 & x - 6 \\ 3 & x \end{matrix} | = 0 \Rightarrow 9 x - 3 (x - 6) = 0 \Rightarrow 9 x - 3 x + 18 = 0 \Rightarrow 6 x = - 18 \Rightarrow x = \frac{- 18}{6} = - 3$