geometry

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Indirect proof given triangle ABC,<B is an obtuse angle prove there can only be one obtuse angle in triangle.

  • geometry -

    Obtuse angles are greater than 90 degrees.
    The sum of all angles in a triangle must be 180 degrees. You can't have two of them > 90 and have a total of 180.

    Another indirect proof: try drawing one.

  • geometry -

    yes

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