are the triangles below acute, obtuse, or right?\ntriangle a\ntriangle b\ntriangle c\ntriangle…

Explanation:

Step1: Recall angle - type definitions

An acute - angled triangle has all angles less than 90°. A right - angled triangle has one angle equal to 90°. An obtuse - angled triangle has one angle greater than 90°.

Step2: Analyze Triangle A

Triangle A has angles 50°, 50°, and 80°. Since all angles are less than 90°, it is an acute - angled triangle.

Step3: Analyze Triangle B

Triangle B has a 90° angle (the right - angle symbol). So, it is a right - angled triangle.

Step4: Analyze Triangle C

Triangle C has a 90° angle (the right - angle symbol). So, it is a right - angled triangle.

Step5: Analyze Triangle D

Triangle D has an angle of 115° which is greater than 90°. So, it is an obtuse - angled triangle.

Answer:

Triangle A: Acute Triangle B: Right Triangle C: Right Triangle D: Obtuse