Question

Theorem:A triangle has at most one obtuse angle.Eduardo is proving the theorem above by contradiction.He began by assuming that in triangle ABC,Which theorem will Eduardo use to reach a contradiction?

Answer 1

Eduardo will use the angle sum property of triangles, which states the sum of the angles in a triangle is 180 degrees, to prove that a triangle cannot have more than one obtuse angle.

Step-by-step explanation:

The student is asking about the properties of triangles and how to prove the theorem that a triangle can have at most one obtuse angle. Eduardo will likely use the fact that the sum of the angles in a triangle is 180 degrees to reach a contradiction. Assuming triangle ABC has two obtuse angles, the sum of these two angles would already exceed 180 degrees, which violates the fundamental property of a triangle. Therefore, this assumption that a triangle can have two obtuse angles leads to a contradiction, and hence a triangle can have at most one obtuse angle.