Answer: Because the 3 angles in a right angle triangle add up to 180 degrees and if an obtuse angle was included then they would add up to over 189 degrees.
Step-by-step explanation: Examples of obtuse angles Angles can also be classified as acute , right, and straight, depending on the measure. When identifying or measuring an obtuse angle, be careful about the rotation from one side of the angle to the other that produces the angle.
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