Question

Find $|z|$, if $z=5-12i:$

• A. $17$
• B. $13$
• C. Both (a) and (b)
• D. $-13$

Answer 1

The correct option is B $13$

$|z|$ is defined as the distance of the complex number $z$ from the origin. So here, $|z|=\sqrt{(5-0{)}^2+(-12-0{)}^2}=\sqrt{25+144}=13.$