Editing Imaginary unit (section)

=== Graphic representation ===
{{main|Complex plane}}
The complex numbers can be represented graphically by drawing the real [[number line]] as the horizontal axis and the imaginary numbers as the vertical axis of a [[Cartesian coordinate system|Cartesian plane]] called the ''[[complex plane]]''. In this representation, the numbers {{math|1}} and {{mvar|i}} are at the same distance from {{math|0}}, with a right angle between them. Addition by a complex number corresponds to [[translation (geometry)|translation]] in the plane, while multiplication by a unit-magnitude complex number corresponds to rotation about the origin. Every [[similarity (geometry)|similarity]] transformation of the plane can be represented by a complex-linear function <math>z \mapsto az + b.</math>