Chapter 6 - Section 6.5 - Complex Numbers in Polar Form; DeMoivre's Theorem - Exercise Set - Page 767: 3

$$|z|=3$$

We plot the complex number $z=3$ the same way we plot $(3,0)$ in the rectangular coordinate system. We find the absolute value of the complex number as follows.$$|z|=|a+bi|=\sqrt{a^2+b^2} \\ \Rightarrow \quad |z|=|3+0i|=\sqrt{3^2+0^2}=3$$