Chapter 6 - Section 6.5 - Complex Numbers in Polar Form; DeMoivre's Theorem - Exercise Set - Page 767: 5

$$|z|=\sqrt{13}$$

We plot the complex number $z=3+2i$ the same way we plot $(3,2)$ in the rectangular coordinate system. We find the absolute value of the complex number as follows.$$|z|=|a+bi|=\sqrt{a^2+b^2} \\ \Rightarrow \quad |z|=|3+2i|=\sqrt{3^2+2^2}=\sqrt{13}$$