The four cardinal directions or cardinal points are north, south, east, and west.

Angle XOP=Θ and angle XOQ=- Θ. From a point in the terminal side of each a perpendicular line is drawn…

Angle XOP=Θ and angle XOQ=90+Θ. From a point in the terminal side of each a perpendicular line is…

Trigonometric reference triangles/angles drawn for 60 degree reference angel in quadrants I and II.

Right triangle OCB that can be used to show the relationships between x, y, r, and Θ.

Special right triangle with angles 30 degrees, 60 degrees, and 90 degrees with side measures/relationships…

Special right triangle with angles 45 degrees, 45 degrees, and 90 degrees with side measures/relationships…