Answer:
The argument is valid by the law of syllogism.
Step-by-step explanation:
Syllogisms work exactly like the example in this exercise: they structure is the following
- Every time
holds, then
holds as well
- Then
So, you're told that whenever a triangle has an obtuse angle, it is called an obtuse triangle.
Then, you're told that triangle ABC has an obtuse angle.
Then, triangle ABC is an obtuse triangle.