Question

If the vector $2i-3j-6k$ and $4i-mj-12k$ are parallel then find $m$.

Answer 1

The vectors are parallel if the drs are proportional

$⟹\frac{2}{4}=\frac{-3}{-m}\frac{-6}{-12}\frac{3}{m}=\frac{1}{2}m=6$