Khan Academy

Determining congruent triangles (K-A)

Triangle congruence postulates/criteria (K-A)

Why SSA isn't a congruence postulate/criterion (K-A)

Corresponding angles in congruent triangles (K-A)

Finding angles in isosceles triangles (example 2) (K-A)

Finding angles in isosceles triangles (K-A)

Isosceles & equilateral triangles problems (K-A)

Intro to angle bisector theorem (K-A)

Using the angle bisector theorem (K-A)

Similar shapes & transformations (K-A)

Determining similar triangles (K-A)

Intro to triangle similarity (K-A)

Proving slope is constant using similarity (K-A)

Triangle similarity postulates/criteria (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)

Challenging similarity problem (K-A)

Using similar & congruent triangles (K-A)

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

Solving similar triangles (K-A)

Intro to the trigonometric ratios (K-A)

Trigonometric ratios in right triangles (K-A)

Right triangle word problem (K-A)

Sine & cosine of complementary angles (K-A)