We are given that,

x ∈ N

We need to find the value of x.

Determinant of 2 × 2 matrix is found as,

So, take

Since,

⇒ 2x² = 8

⇒ x² = 4

⇒ x = ±√4

⇒ x = ±2

Since, x ∈ N

-2 is not a natural number.

Thus, the value of x is 2.