If A is a 2 × 2 matrix such that |A| ≠ 0 and |A| = 5, write the value of |4A|.
Theorem: If A be k × k matrix then |pA|=pk|A|.
Given, p=4,k=2 and |A|=5.
|4A|=42 × 5
=16 × 5
=80