# Angles

## Types of Angles and their Properties

Zero Degree angle- Has an angle size of zero

Acute angle- Has an angle size of more them zero, but less than 90

Right Angle- Has an exact degree of 90, perpendicular to base

Obtuse angle- Has an angle size of more than 90 degrees, but less than 180

Straight angle- Has an exact size of 180 degrees.

Reflex angle- Has an angle size of more than 180 degree, but less than 360.

360 degree angle- Has an angle size of exactly 360, a full circle.

## Important to know

-Angles are measured in degrees

-A ray is a line from an endpoint that goes on endlessly in one direction

-The base line of the angle is called the Initial

-The rising line is called the Terminal

-The point where they meet is called the Vertex

-Angles going anti-clickwise are positive

-Angles going clockwise are negative

-Complementary = 90 degrees

-Supplementary = 180 degrees

-Alternate angles, Adjacent angles, Corresponding, Vertically opposite and Co-interior angles

-The angles in a triangle add up to 180 degrees, the angles in a square add up to 360 degrees