Using Directed Angles

Directed Angles (Incomplete)

What are they?

Directed angles, simply stated are those specially oriented angles which help us deal with nasty configuration cases in a jiffy. These are denoted by the symbol $\measuredangle$ instead of our conventional $\angle$. Directed angles take up any given angle and represent them $\pmod{180^{\circ}}$. But it is to be noted that this form of notation is not standard in math competitions.

We will now move on to the properties associated with directed angles.

Properties

1. Spell it Right: In directed angles, the order in which we name our angles is to be taken into consideration. For instance, we say that $\measuredangle{PQR}$ is positive if the vertices $P,Q,R$ appear in a clockwise manner and negative if otherwise.