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Isosceles and Equilateral Triangles

  • Isosceles Triangle Theorem: If two sides of a triangle are congruent, then the angles opposite those sides are congruent
  • Isosceles Triangle Theorem Converse: If two angles of a triangle are congruent, then the sides opposite those angles are congruent
  • Isosceles Triangle Corollaries:
    • A triangle is equilateral if and only if it is equiangular
    • Each angle of an equilateral triangle measures 60 degrees

Isosceles and Equilateral Triangles

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Mathematics: Geometry