Khan Academy

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

Challenging similarity problem (K-A)

Using similar & congruent triangles (K-A)

Solving similar triangles Video (K-A)

Solving similar triangles: same side plays different roles (K-A)

Hypotenuse, opposite, and adjacent (K-A)

Intro to the trigonometric ratios (K-A)

Trigonometric ratios in right triangles Notes (K-A)

Trigonometric ratios in right triangles Video (K-A)

Angles of elevation and depression (K-A)

Right triangle trigonometry review (K-A)

Right triangle word problem (K-A)

Intro to the Pythagorean theorem (K-A)

Intro to the Pythagorean theorem 2 (K-A)

Introduction to the Pythagorean theorem (K-A)

Pythagorean theorem example (K-A)

Pythagorean theorem II (K-A)

Pythagorean theorem word problem: carpet (K-A)

Pythagorean theorem word problem: fishing boat (K-A)

Another Pythagorean theorem proof (K-A)

Bhaskara's proof of the Pythagorean theorem (K-A)

Garfield's proof of the Pythagorean theorem (K-A)

Pythagorean theorem proof using similarity (K-A)

Sine & cosine of complementary angles Video (K-A)

Trig word problem: complementary angles (K-A)