Question

If $z=6-3i$ find $|z|$

• A. $\sqrt{42}$
• B. $\sqrt{40}$
• C. $\sqrt{38}$
• D. More than $8$

Answer 1

The correct option is A $\sqrt{42}$

Given

$z=6-3i$

The modulus is given as $|z|=\sqrt{x^2+y^2}$

Here $x=6y=-3$

$|z|=\sqrt{6^2+(-3^2)}$

$|z|=\sqrt{36+6}$

$|z|=\sqrt{42}$