Answer
$13$
Work Step by Step
The magnitude of a vector $v=ai+bj$ is: $||v||=\sqrt{a^2+b^2}$.
Hence, here we have
$||v||
\\=\sqrt{(-5)^2+12^2}
\\=\sqrt{25+144}\\
=\sqrt{169}\\
=13$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.