Answer
$|-3+10i|=\sqrt{109}$
Work Step by Step
The absolute value of a complex number
$z=a+bi,$ denoted $|z|,$ is a nonnegative
real number defined as $|z|=\sqrt{a^{2}+b^{2}}$.
$|z|=|-3+10i|$
$=\sqrt{a^{2}+b^{2}}\qquad$ ...substitute $-3$ for $a$ and $10$ for $b$
$=\sqrt{(-3)^{2}+10^{2}}\qquad$ ...simplify.
$=\sqrt{9+100}$
$=\sqrt{109}$
