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Question
Write the sum of the angles of an obtuse triangle.
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Solution
In the given problem, ΔABC is an obtuse triangle, with ∠B as the obtuse angle.

So, according to “the angle sum property of the triangle”, for any kind of triangle, the sum of its angles is 180°. So,
∠A+ ∠B + ∠C = 180°
Therefore, sum of the angles of an obtuse triangle is 180°.
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