Answer
(a) $u$ is a scalar multiple of $z$.
(b) $v$ is a scalar multiple of $z$.
Work Step by Step
(a) since $u=\left(2,4,9\right)=12 \left(\frac{1}{2},-\frac{2}{3},\frac{3}{4}\right)$, then $u$ is a scalar multiple of $z$.
(b) since $v=\left(-1,\frac{4}{3},-\frac{3}{2}\right)=-2 \left(\frac{1}{2},-\frac{2}{3},\frac{3}{4}\right)$, then $v$ is a scalar multiple of $z$.
