Question

Classify the following triangle as acute, obtuse, or right.
51
78
51
A. Obtuse
B. Right
C. Acute
D. None of these

Answer 1

Answer:

C. Acute

Step-by-step explanation:

• Acute angles are less than 90°
• Obtuse angles are greater than 90°, but less than 180°
• Right angles are exactly 90°

Extra:

• Straight angles are exactly 180° (basically a straight line)
• Reflex angles are greater than 180°, but less than 360°