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An exterior angle of a triangle is equal to:

Class 9Exterior Angle of a TriangleGeometry — Lines and Angles
  • Athe interior angle next to it
  • Bthe sum of the two interior opposite angles
  • C180° minus the sum of the interior opposite angles
  • Dhalf the sum of all three angles

Step-by-Step Solution

Exterior angle theorem: if a side of a triangle is produced, the exterior angle formed equals the sum of the two interior opposite angles.
Answer: B) the sum of the two interior opposite angles

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