Could it be in a triangle: one corner is straight and the other two are sharp? Could there be a triangle: one corner is sharp and the other two are straight?
Yes, because a right-angled triangle necessarily has one right angle, which is 90 degrees, and two acute angles, they always add up to 90. For example, 30 and 60 or 45 and 45.
But at the same time, no triangle can have two right angles and one acute one at once, because this contradicts the axioms of a right-angled triangle.
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