math_man
Geometry - Khan Academy
Play
Euclid as the Father of Geometry
Language and Notation of Basic Geometry
Lines, Line Segments, and Rays
Angle Basics
Language and Notation of the Circle
Measuring Angles in Degrees
Using a Protractor
Measuring Angles
Complementary and Supplementary Angles
Angles at the intersection of two lines
Proof-Vertical Angles are Equal
Angles Formed by Parallel Lines and Transversals
Proof - Sum of Measures of Angles in a Triangle are 180
Triangle Angle Example 1
Triangle Angle Example 2
Triangle Angle Example 3
Challenging Triangle Angle Problem
Proof - Corresponding Angle Equivalence Implies Parallel Lines
Finding more angles
Sum of Interior Angles of a Polygon
Congruent Triangles and SSS
SSS to Show a Radius is Perpendicular to a Chord that it Bisects
Other Triangle Congruence Postulates
Two column proof showing segments are perpendicular
Sum of the exterior angles of convex polygon
Finding Congruent Triangles
More on why SSA is not a postulate
Congruent Triangle Proof Example
Congruent Triangle Example 2
Congruent legs and base angles of Isosceles Triangles
Equilateral Triangle Sides and Angles Congruent
Equilateral and Isosceles Example Problems
Another Isosceles Example Problem
Example involving an isosceles triangle and parallel lines
Figuring out all the angles for congruent triangles example
Perimeter and Area Basics
Triangle Area Proofs
Interesting Perimeter and Area Problems
Koch Snowflake Fractal
Area of an Equilateral Triangle
Area of Koch Snowflake (part 1) - Advanced
Area of Koch Snowflake (part 2) - Advanced
Challenging Perimeter Problem
Similar Triangle Basics
Similarity Postulates
Similar Triangle Example Problems
Similarity Example Problems
Challenging Similarity Problem
Similarity example where same side plays different roles
Finding Area Using Similarity and Congruence
Pythagorean Theorem Proof Using Similarity
30-60-90 Triangle Side Ratios Proof
45-45-90 Triangle Side Ratios
30-60-90 Triangle Example Problem
The Golden Ratio
Introduction to angles (old)
Angles (part 2)
Angles (part 3)
Angles formed between transversals and parallel lines
Angles of parallel lines 2
The Angle Game
Similar triangles
Similar triangles (part 2)
Angle Game (part 2)
Acute Right and Obtuse Angles
Area and Perimeter
Circles: Radius, Diameter and Circumference
Area of a circle
The Pythagorean Theorem
Pythagorean Theorem II
45-45-90 Triangles
Intro to 30-60-90 Triangles
30-60-90 Triangles II
Solid Geometry Volume
Cylinder Volume and Surface Area
Heron's Formula
Part 1 of Proof of Heron's Formula
Part 2 of the Proof of Heron's Formula
Inscribed and Central Angles
Area of Inscribed Equilateral Triangle (some basic trig used)
Right Triangles Inscribed in Circles (Proof)
Area of Diagonal Generated Triangles of Rectangle are Equal
Triangle Medians and Centroids
Triangle Medians and Centroids (2D Proof)
Rhombus Diagonals
2003 AIME II Problem 7
Perpendicular Radius Bisects Chord
Circumcenter of a Triangle
Circumcenter of a Right Triangle
Three Points Defining a Circle
Point Line Distance and Angle Bisectors
Incenter and incircles of a triangle
Angle Bisector Theorem Proof
Inradius Perimeter and Area
Angle Bisector Theorem Examples
Medians divide into smaller triangles of equal area
Exploring Medial Triangles
Proving that the Centroid is 2-3rds along the Median
Median Centroid Right Triangle Example
Proof - Triangle Altitudes are Concurrent (Orthocenter)
Review of Triangle Properties
Euler Line
Euler's Line Proof
Common Orthocenter and Centroid
Quadrilateral Overview
Proof - Opposite Sides of Parallelogram Congruent
Proof - Diagonals of a Parallelogram Bisect Each Other
Proof - Opposite Angles of Parallelogram Congruent
Proof - Rhombus Diagonals are Perpendicular Bisectors
Proof - Rhombus Area Half Product of Diagonal Length
Area of a Parallelogram
Problem involving angle derived from square and circle
Area of a Regular Hexagon
1
2
3
4
5
6
7
8
9
10
Prev
Next
powered by
Huzzaz