## Precalculus (6th Edition) Blitzer

A complex plane has two axes: one is the real $x$ -axis and the other is the imaginary $y$ -axis. When a complex number is written in rectangular form $\left( a+ib \right)$, then its real part $\left( a \right)$ represents the real $x$ coordinate and the imaginary part $\left( b \right)$ represents the imaginary $y$ coordinate of a point. In this way, a complex number is plotted in the complex plane.