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Geometry by khanacademy
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Geometry by khanacademy
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  1. ▶ Euclid as the Father of Geometry by khanacademy
  2. 2 Language and Notation of Basic Geometry by khanacademy
  3. 3 Lines, Line Segments, and Rays by khanacademy
  4. 4 Language and Notation of the Circle by khanacademy
  5. 5 Angle Basics by khanacademy
  6. 6 Measuring Angles in Degrees by khanacademy
  7. 7 Using a Protractor by khanacademy
  8. 8 Measuring Angles by khanacademy
  9. 9 Complementary and Supplementary Angles by khanacademy
  10. 10 Angles at the intersection of two lines by khanacademy
  11. 11 Proof-Vertical Angles are Equal by khanacademy
  12. 12 Angles Formed by Parallel Lines and Transversals by khanacademy
  13. 13 Proof - Sum of Measures of Angles in a Triangle... by khanacademy
  14. 14 Triangle Angle Example 1 by khanacademy
  15. 15 Triangle Angle Example 2 by khanacademy
  16. 16 Triangle Angle Example 3 by khanacademy
  17. 17 Challenging Triangle Angle Problem by khanacademy
  18. 18 Proof - Corresponding Angle Equivalence Implies... by khanacademy
  19. 19 Finding more angles by khanacademy
  20. 20 Sum of Interior Angles of a Polygon by khanacademy
  21. 21 Congruent Triangles and SSS by khanacademy
  22. 22 SSS to Show a Radius is Perpendicular to a Chor... by khanacademy
  23. 23 Other Triangle Congruence Postulates by khanacademy
  24. 24 Two column proof showing segments are perpendic... by khanacademy
  25. 25 Sum of the exterior angles of convex polygon by khanacademy
  26. 26 Finding Congruent Triangles by khanacademy
  27. 27 More on why SSA is not a postulate by khanacademy
  28. 28 Congruent Triangle Proof Example by khanacademy
  29. 29 Congruent Triangle Example 2 by khanacademy
  30. 30 Congruent legs and base angles of Isosceles Tri... by khanacademy
  31. 31 Equilateral Triangle Sides and Angles Congruent by khanacademy
  32. 32 Equilateral and Isosceles Example Problems by khanacademy
  33. 33 Another Isosceles Example Problem by khanacademy
  34. 34 Example involving an isosceles triangle and par... by khanacademy
  35. 35 Figuring out all the angles for congruent trian... by khanacademy
  36. 36 Perimeter and Area Basics by khanacademy
  37. 37 Triangle Area Proofs by khanacademy
  38. 38 Interesting Perimeter and Area Problems by khanacademy
  39. 39 Koch Snowflake Fractal by khanacademy
  40. 40 Area of an Equilateral Triangle by khanacademy
  41. 41 Area of Koch Snowflake (part 1) - Advanced by khanacademy
  42. 42 Area of Koch Snowflake (part 2) - Advanced by khanacademy
  43. 43 Challenging Perimeter Problem by khanacademy
  44. 44 Similar Triangle Basics by khanacademy
  45. 45 Similarity Postulates by khanacademy
  46. 46 Similar Triangle Example Problems by khanacademy
  47. 47 Similarity Example Problems by khanacademy
  48. 48 Challenging Similarity Problem by khanacademy
  49. 49 Similarity example where same side plays differ... by khanacademy
  50. 50 Finding Area Using Similarity and Congruence by khanacademy
  51. 51 Pythagorean Theorem Proof Using Similarity by khanacademy
  52. 52 30-60-90 Triangle Side Ratios Proof by khanacademy
  53. 53 45-45-90 Triangle Side Ratios by khanacademy
  54. 54 30-60-90 Triangle Example Problem by khanacademy
  55. 55 The Golden Ratio by khanacademy
  56. 56 Introduction to angles (old) by khanacademy
  57. 57 Angles (part 2) by khanacademy
  58. 58 Angles (part 3) by khanacademy
  59. 59 Angles formed between transversals and parallel... by khanacademy
  60. 60 Angles of parallel lines 2 by khanacademy
  61. 61 The Angle Game by khanacademy
  62. 62 Similar triangles by khanacademy
  63. 63 Similar triangles (part 2) by khanacademy
  64. 64 Angle Game (part 2) by khanacademy
  65. 65 Acute Right and Obtuse Angles by khanacademy
  66. 66 Area and Perimeter by khanacademy
  67. 67 Circles: Radius, Diameter and Circumference by khanacademy
  68. 68 Area of a circle by khanacademy
  69. 69 The Pythagorean Theorem by khanacademy
  70. 70 Pythagorean Theorem II by khanacademy
  71. 71 45-45-90 Triangles by khanacademy
  72. 72 Intro to 30-60-90 Triangles by khanacademy
  73. 73 30-60-90 Triangles II by khanacademy
  74. 74 Solid Geometry Volume by khanacademy
  75. 75 Cylinder Volume and Surface Area by khanacademy
  76. 76 Heron's Formula by khanacademy
  77. 77 Part 1 of Proof of Heron's Formula by khanacademy
  78. 78 Part 2 of the Proof of Heron's Formula by khanacademy
  79. 79 Inscribed and Central Angles by khanacademy
  80. 80 Area of Inscribed Equilateral Triangle (some ba... by khanacademy
  81. 81 Right Triangles Inscribed in Circles (Proof) by khanacademy
  82. 82 Area of Diagonal Generated Triangles of Rectang... by khanacademy
  83. 83 Triangle Medians and Centroids by khanacademy
  84. 84 Triangle Medians and Centroids (2D Proof) by khanacademy
  85. 85 Rhombus Diagonals by khanacademy
  86. 86 2003 AIME II Problem 7 by khanacademy
  87. 87 Perpendicular Radius Bisects Chord by khanacademy
  88. 88 Circumcenter of a Triangle by khanacademy
  89. 89 Circumcenter of a Right Triangle by khanacademy
  90. 90 Three Points Defining a Circle by khanacademy
  91. 91 Point Line Distance and Angle Bisectors by khanacademy
  92. 92 Incenter and incircles of a triangle by khanacademy
  93. 93 Angle Bisector Theorem Proof by khanacademy
  94. 94 Inradius Perimeter and Area by khanacademy
  95. 95 Angle Bisector Theorem Examples by khanacademy
  96. 96 Medians divide into smaller triangles of equal ... by khanacademy
  97. 97 Exploring Medial Triangles by khanacademy
  98. 98 Proving that the Centroid is 2-3rds along the M... by khanacademy
  99. 99 Median Centroid Right Triangle Example by khanacademy
  100. 100 Proof - Triangle Altitudes are Concurrent (Orth... by khanacademy
  101. 101 Review of Triangle Properties by khanacademy
  102. 102 Euler Line by khanacademy
  103. 103 Euler's Line Proof by khanacademy
  104. 104 [Deleted Video] by
  105. 105 Common Orthocenter and Centroid by khanacademy
  106. 106 Quadrilateral Overview by khanacademy
  107. 107 Proof - Opposite Sides of Parallelogram Congruent by khanacademy
  108. 108 Proof - Diagonals of a Parallelogram Bisect Eac... by khanacademy
  109. 109 Proof - Opposite Angles of Parallelogram Congruent by khanacademy
  110. 110 Proof - Rhombus Diagonals are Perpendicular Bis... by khanacademy
  111. 111 Proof - Rhombus Area Half Product of Diagonal L... by khanacademy
  112. 112 Area of a Parallelogram by khanacademy
  113. 113 Problem involving angle derived from square and... by khanacademy
  114. 114 Area of a Regular Hexagon by khanacademy
 

Euclid as the Father of Geometry

khanacademy khanacademy·3,519 videos
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Uploaded on Feb 28, 2012

Learn more: http://www.khanacademy.org/video?v=Wq...
Euclid and his Elements (and how much Abraham Lincoln liked them)

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Top Comments

  • Unit1262

    Unit1262 1 year ago

    Khan Academy has got everything! Khan Academy, what is the meaning of life?

    · 40

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  • anonymousbl00dlust

    anonymousbl00dlust 1 year ago

    will you ever do a series on non-euclidean geometry?

    · 22

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All Comments (147)

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  • Randevous223

    Randevous223 3 weeks ago

    42

    · 2

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    in reply to Unit1262 (Show the comment)
  • blazejames47

    blazejames47 3 weeks ago

    One of these days I'm gonna go back in time and shove a broom up his ass

    ·

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  • StiegeNZ

    StiegeNZ 3 months ago

    Yeah, I'd really appreciate something on Differential Geometry and Tensors.

    ·

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    in reply to anonymousbl00dlust (Show the comment)
  • James Booher

    James Booher 5 months ago

    Man, I always wanted to learn more than was traditionally thought needed for my age group (Freshmen in High School) so now I'm going to use my thanksgiving break to learn from Geometry up through Probability and Statistics, Breaking the system FTW!!! (My math teacher is gonna be mad...)

    ·

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  • DKM101

    DKM101 5 months ago

    Do it! And computer science!

    ·

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    in reply to lettersfromkyle (Show the comment)
  • skwuim

    skwuim 6 months ago

    Whether Euclid was the father of Geometry is disputable, however it is safe to say he was a big role in it.

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  • thetrue sleuth

    thetrue sleuth 6 months ago

    He has already answered you're question by creating Kahn Academy.

    ·

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    in reply to Unit1262 (Show the comment)
  • roger rafael

    roger rafael 7 months ago

    thales introduced geometry in greece.

    ·

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  • roger rafael

    roger rafael 7 months ago

    thales must be the father of geometry......

    ·

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  • JasJumbie

    JasJumbie 7 months ago

    me thats why im here =(

    ·

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    in reply to Tom Vanderploeg (Show the comment)
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