Answer
$\lt 6,-8 \gt$ and $10$
Work Step by Step
The formula to find the magnitude of a vector is:
$|n|=\sqrt{n_1^2+n_2^2}$
Here, $-2u=-2\lt -3,4 \gt =\lt 6,-8 \gt$
and $|\lt 6,-8\gt|=\sqrt{(6)^2+(-8)^2}=\sqrt {100}=10$
Hence, our final answers are: $\lt 6,-8 \gt$ and $10$
