Question

m∠abc = 45°
what type of angle is it?
obtuse
straight
right
acute

Explanation:

Step1: Recall angle definitions

• Acute angle: \(0^{\circ}<\theta < 90^{\circ}\)
• Right angle: \(\theta=90^{\circ}\)
• Obtuse angle: \(90^{\circ}<\theta < 180^{\circ}\)
• Straight angle: \(\theta = 180^{\circ}\)

Step2: Compare given angle

Given \(m\angle ABC = 45^{\circ}\). Since \(0^{\circ}<45^{\circ}<90^{\circ}\), it is an acute angle.

Answer:

D. acute