For what value of $k$ is the determinant of \begin{bmatrix}5 & 2\4 & kend{\bmatrix} zero?

Step-by-step solution

1. Compute the determinant: $\det =;5k-2\times 4=5k-8$
2. Set the determinant equal to zero: $5k-8=0$
3. Solve for $k$: $k=\frac{8}{5}$

Concept tested: Determinant zero condition

Published 5 September 2026 · Last updated 16 September 2026 · How this solution was prepared and checked