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Lesson 2: The sum of interior angles of triangle

Author:Jinqliu
Topic:Angles

New Resources

  • Circle Passing Through 3 Points
  • Reflection = 180° Rotation about a Line
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  • Reflection across a line
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Discover Resources

  • Centers of a Triangle
  • #25 Mirror-image Triangles with Circumcircles
  • Interactive Rectangle (integers)
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  • Flatten the curve

Discover Topics

  • Vectors
  • Derivative
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