Explaining the trigonometric ratios of right triangles for sine, cosine, and tangent

Finding the six trigonometric ratios for a right triangle

Using trig to find the length of the side of a right triangle given an angle and side length

Using trig to find an angle in a right triangle with two given sides

Explaining the Pythagorean Theorem and using it to find a missing side in a right triangle

Explaining the special right triangles and the relationships between their sides

Special Right Triangles Exercise 1

Special Right Triangles Exercise 2

Defining radians for angle measure using the corresponding arc length on a unit circle