# How do you find abs( 9 + 4i )?

$| 9 + 4 i | = \sqrt{97}$
$| a + b i |$ is the absolute value or modulas of complex number $a + b i$
and is given by $\sqrt{{a}^{2} + {b}^{2}}$
Hence $| 9 + 4 i | = \sqrt{{9}^{2} + {4}^{2}} = \sqrt{81 + 16} = \sqrt{97}$