High school geometry videos

Intro to Euclidean geometry

Introduction to rigid transformations

Translations

Rotations

Reflections

Dilations

Rigid transformations overview

Dilation preserved properties

Properties & definitions of transformations

Symmetry

Proofs with transformations

Transformations & congruence

Triangle congruence from transformations

Congruent triangles

Theorems concerning triangle properties

Working with triangles

Theorems concerning quadrilateral properties

Proofs of general theorems

Constructing lines & angles

Definitions of similarity

Introduction to triangle similarity

Solving similar triangles

Angle bisector theorem

Solving problems with similar & congruent triangles

Proving relationships using similarity

Solving modeling problems with similar & congruent triangles

Pythagorean theorem

Pythagorean theorem proofs

Special right triangles

Ratios in right triangles

Introduction to the trigonometric ratios

Solving for a side in a right triangle using the trigonometric ratios

Sine & cosine of complementary angles

Solving for an angle in a right triangle using the trigonometric ratios

Modeling with right triangles

Distance and midpoints

Dividing line segments

Problem solving with distance on the coordinate plane

Parallel & perpendicular lines on the coordinate plane

Equations of parallel & perpendicular lines

Graphs of circles intro

Standard equation of a circle

Expanded equation of a circle

Focus and directrix of a parabola

Circle basics

Arc measure

Arc length (from degrees)

Introduction to radians

Arc length (from radians)

Sectors

Inscribed angles

Inscribed shapes problem solving

Proofs with inscribed shapes

Properties of tangents

Constructing regular polygons inscribed in circles

Constructing circumcircles & incircles

Constructing a line tangent to a circle

2D vs. 3D objects

Cavalieri's principle and dissection methods

Volume and surface area

Density