If the matrix A = [(6,x,2), (2,-1,2), (-10,5,2)] is a singular matrix, Find the value of x.

Question

If the matrix A = \(\begin{bmatrix} 6& x & 2 \\ 2 & -1 & 2 \\ -10 & 5 & 2 \end{bmatrix}\) is a singular matrix, Find the value of x. 

Answer 1

A is a singular matrix

∴ |A| = 0

⇒ 6(-12) - x (24) + 2(0) = 0

⇒ -24x = 72

x = -3