Khan Academy

Challenging similarity problem (K-A)

Geometry word problem: a perfect pool shot (K-A)

Geometry word problem: Earth & Moon radii (K-A)

Geometry word problem: the golden ratio (K-A)

Intro to angle bisector theorem (K-A)

Using similar & congruent triangles (K-A)

Using the angle bisector theorem (K-A)

Pythagorean theorem proof using similarity (K-A)

Simplifying square roots (K-A)

Simplifying square roots (variables) (K-A)

Simplifying square-root expressions (K-A)

Hypotenuse, opposite, and adjacent (K-A)

Intro to the trigonometric ratios (K-A)

Solving for a side in right triangles with trigonometry (K-A)

Solving for a side in right triangles with trigonometry-video (K-A)

Triangle similarity & the trigonometric ratios (K-A)

Trigonometric ratios in right triangles (K-A)

Trigonometric ratios in right triangles- video (K-A)

30-60-90 triangle example problem (K-A)

Sine & cosine of complementary angles (K-A)

Special right triangles intro (part 1) (K-A)

Special right triangles intro (part 2) (K-A)

Special right triangles proof (part 1) (K-A)

Special right triangles proof (part 2) (K-A)

Trig word problem: complementary angles (K-A)