Condition for Complex Number to be in Right Half Plane

Theorem
Let $\C$ be the complex plane.

Let $P$ be the half-plane of $\C$ to the right of the infinite straight line $x = \lambda$.

The points in $P$ can be defined by:
 * $\operatorname{Re} \left({z}\right) > \lambda$

where $\operatorname{Re} \left({z}\right)$ denotes the real part of $z$.